The following is information sent to me from EDGE RAT.

This is the methods he used for lowering his truck.

As for the front:
1) Lift the front end up and put it on jack stands. Block rear wheels so that the truck doesn't roll off the jack stands. Let front wheels hang.
2) Get 1/2" socket to remove the cover plate on the torsion bar adjuster.
3) Remove torsion bar adjuster bolt (if you haven't already)
4) Get 2 or 3 jaw gear puller. Set 'arms' on outside of trans crossmember right where torsion bar adjuster plate is. Screw the threaded rod up until it hits the torsion bar adjuster. Do not go through the support plate that is under the torsion bar key. You will need to remove this so that you can remove the key and flip it.
5) Once you remove the plate, slowly loosen the torsion bar key. Do it slowly so that it does not snap back and potentially injure you. Remove torsion bar key, and flip it over. Re-install key onto torsion bar. There is no need to try and 're-index' torsion bar.
6) Reverse removal procedure to install everything. Repeat for other side.
7) Do NOT re-install adjuster bolt. There is no need. It is unnecessary
8) Remove front factory bumpstops and replace them with low profile ones. These can be bought from any 'performance' shop.

The following is the methods EDGE RAT used for helping correct camber issues.

Once all is said and done, you will have a lot of negative camber. The following should be done at a competent alignment shop.
Here is a How-To to fix that as well.:
1) Purchase (from auto parts store or dealer) one pass side upper control arm for torsion bar front end. This has the bigger balljoint, and the whole control arm is a two-piece unit.
2) Purchase caster/camber adjuster kit.
3) Remove factory driver side upper control arm. Install 'new' pass side control arm on driver side.
4) Install new caster/camber kit into factory control arm mounting holes. Make sure they are set at neutral. This will allow for fine tuning once you're done.
5) Separate control arms on both sides so that you now have four pieces that make up the control arms. (of course this is after you remove the upper balljoint from the spindle)
6) Install longer bolts and 1.5-2" spacers/washers, etc. between two parts of the control arms. Re-install 'outer' part of control arm.
7) Install upper balljoint back into spindle.
8) You should be close to 1-2 deg negative camber at this time. Finalize alignment with the new caster/camber bolts.

The following information is what EDGE RAT done to drop the back end.

He installed a set of bell tech 3 inch dropped leafs and removed the lift blocks yielding a 5 inch total drop.

Information credit goes to : rubydist



Front
The front suspension has short / long arms with a torsion bar spring. The torsion bar lays inside the frame rail and is anchored to the frame at the rear. Conveniently, at the rear there is an adjusting bolt that is used at the factory to set the ride height. Once you have located this bolt, you may discover that the settings from one side to the other are quite different. This is due to the large tolerances in the manufacture of the whole torsion spring system. In my case, the left bolt was nearly all the way in, and the right bolt was closer to all the way out. If you find this situation, taking out the adjuster bolts as suggested by EDGE RAT will NOT work. Depending upon what your situation is, you should be able to lower the front end by at least 2" and possibly as much as 5" before you need to flip the torsion keys. This is probably all the lower you will be able to go without other significant modifications, so for most 4x4 lowering, flipping the torsion key will probably not come into play. 4 turns on the adjuster bolt resulted in just over 1" of drop on my truck (counter clockwise is lower.) The adjuster bolts have thread-locker on them, so do not put any oil, etc. on them, and try not to move them any more times than you must, since Ford says they should be replaced if they are turned at all. To adjust this bolt, put a jack under the front crossmember and raise the vehicle to get the weight off the wheels, then turn the bolts. Turning the bolt on each side exactly the same amount should cause both sides to change the same amount, but measure to be sure.

One of the negatives to a torsion spring is they tend to have relatively limited travel. On the Ranger, from the stock loaded height to fully compressed is only about 3" of wheel travel. After about 2" the bump stop touches. My lower A arm showed that the bump stop was hardly ever touching before lowering, after lowering just driving onto the street from my driveway causes the bump stop to touch. They may need to be shaved down... The main purpose of the stop is to prevent over-twisting of the spring, so shaving it should be okay - it doesn't appear that there are any issues with things crashing if it is shaved some. There are also aftermarket (shorter) stops available according to EDGE RAT, but if you install one of those make sure you don't allow too much travel causing the spring to be over-twisted.

There have been posts that suggest that lowering a 4x4 will result in the half shaft joints wearing prematurely. This is unlikely unless you lower it a large amount. On the stock 4x4, the half shaft angles down from the differential to the wheel. Lowering the truck 1" actually straightens out this angle, so for drops of 2" or less, the half shaft angles will be similar to stock. However, the off-road guys say that the half shafts are sensitive to high angles, so if you go lower than 2" you should expect premature joint wear. Lowering 1" like I have done results in the tire never having to get up inside the fender opening, so there are no clearance issues with stock size tires.

Rear
The rear suspension on the 4x4 has a block between the axle and the spring to raise the vehicle. I have seen several posts referring to this as a 2" block, but on my truck it actually measures 2 5/8" - removing this lowers the rear by over 2.5". The 4x4 shock is too long to be used, so I purchased a set of good 2wd shocks. On my truck, the U-bolts did not have enough thread to allow me to use them without the block, so I had to purchase a set of those and cut them to the right length. I jacked up the truck and put jackstands under the frame, then put a jack under the differential. Make sure that you get it up high enough, since you have to allow the axle to go down to the point where all the weight is off the springs in order to get the block out. I did one side at a time so I never had to wrestle the axle around.

At this point, you have a rear spring setup just like a stock 2wd, so if you want to go lower, you can do all of the things that are discussed in other posts regarding lowering 2wd trucks.

Other considerations
After you lower it, be sure to adjust your headlights or else you'll blind the poor sap that meets you as you're cruising around tonight. Also, be sure to follow all safety precautions, i.e. work on level surface, use wheel chocks, use jackstands, keep small children away, etc. to ensure that no one gets hurt while you are doing this project. If it goes like mine, you'll spend more time collecting the parts and tools needed than you will actually doing the lowering.