This is a good point that I haven't thought about. And would be the easiest most direct route to exit the exhuast, I was pillaging around a area at work that stuff gets piled up and never used and I found a couple 5 inch rain caps that have been long forgotten that I saved just in case i decided to take it thru the top of the fenders and they would be easily removable for track outings.

Guys I can easily neck the pipe down to 4 inch if theres a need to. But in my opinion and correct me if im wrong a big block Chrysler proforms at its best with a good flowing exhaust ie big header tubes and the least restrictions as possible. Now a turbo car doesnt need the big primary tubes and the larger tubes and actually hurt your turbo spool characteristics. So IMO if I can fit the 5 inch pipe where it needs to go why not take advantage of the possible gains that running a free flowing setup might give me, and to my limited knowledge theres no downside to running to big of a downpipe.
Future plans are to run a aftermarket block with a 4.5 inch bore.....

Thanks and keep your opinions and ideas coming
Aaron