Rear crossover pipe????

Also, don't forget headers. I'm not familiar with the present generation of Chevy stuff, but the old traditional SB Chevs, a header for one of those is VERY close to the same port spacing of a SB Mopar. I had a 340 in a FJ --40 Landcruiser, and used "Jeep swap" SB Chev headers. just welded the Chev flange to a blank Mopar flange and did some grinding. The middle two bolts even line up!!!!

This is a "converted" Chev to Mopar fit header. The top, middle flange is the original Chev flange