2003 ecsb 2wd
I installed a belltech 3-4 kit on my truck
It came with coils up front and shackles and hangers out back
Im running 20" gmc wheels with 275 45 20 tires
After installing the kit the front was pretty low. Tires would rub the inner fenders if i hit a bump.
So i installed two coil spring boosters in each coil and now its level.about 2" inchs of fender gap f/r
Well now im considering going with a 275 40 20 tire and removing the boosters up front
But what else can i do to bring the rear down about 1 inch? Just so its not raked real bad? Im planning on leaving the 45s on the rear

 

The only think i could think of was to go to a 3 inch shackle out back?
But then im back to messing with the pinion angle

 

I think you'll find that the 3" shackles will not work without modification of the bed floor.

Regarding the front tire rub, I suspect you aren't going to completely solve the problem by going to a shorter tire. Wheel offset/backspace selection makes all the difference. Assuming you're not using OEM wheels, you should compare the offset to same width stockers. That should guide you in the right direction.

Edit: Just noticed you're running GMC wheels. You might try 1/4" spacers behind the wheels. Don't go any thicker with stock wheel studs.

 

The issue with the front will be fine after the smaller tire
Problem is getting the down about a inch more?
Im thinking putting my stock hangers and shackles back on and doing a flip kit is my only option?