Originally Posted by 86toylet
Another pointer. Before you drill, stack all four plates together and match drill them all at once. This will ensure all the holes line up perfectly.
Yes, I actually tack weld all 4 side plates together and then drill them all at once. I use 3/8" x 2 " flat bar for mine. Tricky part is getting the right sized drill bit (18mm) for the larger holes. And some of the later model trucks have bent sided shackles (wider at the top than bottom). Also, I like to add tabs beside the bolt heads to keep them from rotating inside the side plates:
Helps to keep the lock nuts from loosening up on the bolts and vastly diminishes wear as the hardened bolt rotates inside the mild steel side plate: