I have a '75 Duster that I was wanting to get a little more tire under. I have a 68 B body 8 3/4 with an 8" wheel and 5.5 offset with a 28 x 10.5 ET drag. I am wanting to see if I could get 28 x 10.5W in there, but I only have about an inch from the tire to the springs. If I were to go with a an offset shackle and front mount do I have to move the spring pads on the rearend? I just want to get to the back of the factory wheelwell. I was hoping I could do it without having to perform any welding.

Just installed a set of offset shackles and front spring brackets on a 68 Hemi Cuda and gained 3/4"+. You will have to relocate the spring pads on the rearend housing

dr diff has a real nice offset shackle kit

Sorry , they have to be welded, no way around that.

Make sure if you go with the off set, to remove your electronic ignition box ie: MSD-Accel, etc from the car entirely before welding the perches.

Dr. Diff is your man for the right parts and information the first time.

Dr Diff's parts work great...and he has a painless method for laying out the spring mounts on the rear end housing.

Yes they have to be welded and it's a good time to set the pinion angle.