I'm planning an aftermarket k member so I don't think the torsion bar will be a problem. I assume the bellhousing on the 2010 Challenger is much bigger than the QuickTime recommended in this thread? Is that the main difference?
Okay, you'd be good on the suspension front then at least. Not sure what exhaust clearance is like with a passenger side starter, but I guess if it fits on the driver side with steering as well that you could make something work. I believe the factory clutch is something like 11"+, so the bellhousing just stays "fatter" for a longer distance whereas the small block style tapers down quicker. They both have the same bolt pattern for attaching to the block, so they can't be too wildly different in overall diameter. I think the Challenger setup might be a dual disk clutch as well, so it may be longer which could be more the issue than diameter.