Axle perch location

[DukeBoy88]

I'm rebuilding a 14-bolt from an 84 crew cab with CL to CL distance of 40" between axle perchs. what is the CL to CL distance between the perchs of an '88 GMC K5? My plan is to mock up the axle in place, and rotate it so it aligns with the driveshaft, tighten the u-bolts and place the weight of the vehicle on the axle, make adjustments and tack weld the perchs in place and then take it to the welding shop and have them finish it. Anyone see any problems with this method. thanks in advance.

 

[imiceman44]

For a K5 you want 42.5" CL to CL

 

[R72K5]

42.5" center to center of leaf packs is what is needed,
40" was 1 ton all years and 4x4 before 73

just to help verify*