For consideration I offer this..................................

I want to take the "sport" leafs off my 99 Splash and use the springs from my 91 instead. The 91 has 3 springs and a flat and the Splash has 2 and a flat.
Question:
Has anyone done this or know how much stiffer the ride will be??
The truck bottoms the flat spring, as is. Toolbox is full and heavy.
I love the soft ride but can't stand to bottom...ever!!!. Tried helper springs but rode like a hardtail Harley.

Thanks, in advance, for the opinions ya'll

You could just pickup the overload leaf for a standard '99 or even a Tokico overload leaf (better choice) from stylinconcepts.com. You might want to look at the leaf springs off a newer extended cab. Even with the extra leaf on the 91, I'm not sure how much, if any, stiffer it's gonna be. You need to take into consideration the dimensions of the springs, not just how many leaves are there.