The picco p2 or works p2 for the maxx is a direct drop in. Uses the stock maxx clutch parts, header, and pipe(you might want to upgrade the pipe for better performance). You can also use the ezstart on those engines. Nice settup, good performance and looks sweet....comes with its own custom motor mount for the maxx.
Sorry, I see you are worried more about the body then the direct drop in. It will work fine with you stock or aftermarket body for the maxx, might neet to cut the hole bigger for the head to fit through it.