Very nice job here. I earn my living modifying things and it is nice to see someone who is not afraid to cut in to get a job done.
If I were to critique the exhaust, running 2 1/2 back from the engine to a Magnaflow 12288 or similar that would give a 3" outlet would give you a more balanced flow with no loss of power. If the engine was another 20hp more then 2 3/4 front pipes would be in order. Magnaflow does make plenty of dual in dual out mufflers that would have lowered your workload a bit. But I do again have to say, nice job here.
Good job getting the driveline to set in place and keeping the length in order. I am looking forward to how you go about your next step in axles.