Is it cheaper or not worth it?
Those come with Dana 44's
Neither will have a torque arm mount and the cost to properly weld on onto cast iron, cut it to length, weld the housing ends on....you'd end up with something questionable for about the same price as buying one made for an F-Body.
Yea, even if your friend, brother, dad, whoever owns a machine shop chances are it's not going to get set up right unless they specialized in rear housing modifications and if that were the case you wouldn't be asking the question to begin with.

