Rear Shackle Mod

Would it be possible to bolt a new set of shackles to the outside of the frame rail connection point? As you all know, the shackles are narrow at the top (and bolt inside) and wider at the leafs. Why or why would this not work?

TIA

http://www.naxja.org/forum/showthread.php?t=23559&highlight=shackle+mount

scroll down a ways, check out CRASH's solution. This would be a lot stronger, more adjustable, and it won't hang up on your rear bumper or rear bulkhead.