[Busted Knuckles 65]

I ended up buying the 4 inch drop leaf spring from GMC Paul's website. Fit perfectly and bolted up nicely without any modifications. I ended up using the original shackles, just replaced the bushings, which I got from Advance Auto Parts. I replaced the original mounting hardware, which is 9/16 inch diameter bolts. Had to get them at Fastenal, as the local hardware shops don't carry that size. Attached is my truck after the leaf spring replacement as well as a 2 1/2 inch drop spindle install.