One thing that I know you'll have to change is the steering shaft. On a small block conversion, it is V-E-R-Y close, so I'm sure you'll have to re-route the steering with new shafting and u-joints. I doubt that you'll have room for conventional headers, maybe you could cobble up some fenderwell headers. I would also think that you would have trouble fitting the radiator without either moving it forward or cutting the firewall and moving the engine back. Other than that, I don't think I've ever seen this done. Maybe some of the other members can chime in.....