Widen the rear wells

A wooden rolling pin works like a wooden baseball bat and is much easier to handle.
It helps if you have bare metal and a torch to heat up the metal, but yes rumblefish is right.

Eastwood sells a professional, adjustable lip roller for about $300.oo

That's alot of money to use a tool once, but if you want it done right, sometimes to gotta step up to the plate.

I would go with the offset shackles first and give that a try.