need help
 

need some help with building my prostreet truck...first off it is a 69 chevy swb on a 71 chassis, i have cut the floor of the bed to the frame ,have my tubs welded already,i have 15x12 rims with 29/15.5/15 mickeys,i put them on the truck and the tires stick out like 2inches past the bed..i am trying to figure out backspacing..i do not really want to cut the rearend..trying to do this on a budget...any help is greatly appreciated

Wheels
 

Lay the Tire and Wheel down on the Floor,Inside up.Lay a Straight Edge on the Wheel Lip,take your Tape measure and measure to the Mounting flange.If you have say 4"s?Then i would go with 7"s that way you still have 1" inside the Bed lip.If you would want 2"s to the Outer Lip then you Need 8"s of backspace.
Hope that HELPS?
Later
G 8)

If you screw up, Jeg's sells spacers up to 1" thick. Good luck, Dave