91 Gmc C1500 2/4 drop

[skrapjp]

I'm new to lowering vehicles so i need some advice. I dropped my gmc c1500 ext. cab with 2" drop spindles. The problem i'm having is my wheels are rubbing with my lower control arms when just slighty turning. I was planning on keeping the stock wheel for a while, but they have to much backspacing. They are 15" and have 4.5" backspacing the kit i have states not to use wheels with more than 3.5". is there any thing i can do like grind my control arm down, do you think a 1/2 spacer would be a big help??? i'm just trying to avoid buy new wheels right now.