One option is to use a sleeve inside the bushing (some bushings come w/ sleeves).

Another option is a bolt and lock nut, tighten the nut to just compress the bushing and use it like that. I add anti-rotation tabs to hold the bolt head still inside the shackle and that helps keep it from loosening:

[Linked Image]

http://www.4crawler.com/4x4/ForSale/Shackles.shtml