So instead of backtracking details, for now, lets just jump in where I'm tying up loose ends.
Exhaust. Due to time constraints I was nearly resigned to use an NOS muffler on this project until I found that it interferes with the electric clutch. An option I always considered was just straight-piping the engine, however plowing in a group would require that I hand out earplugs. I needed to at least make something that attenuated the exhaust note, and better yet deepen the note.
Harley drag pipe baffles- seemed simple enough. Bolt a 7ga flange to the block, weld a section of 1-3/8" mandrel bend, transition to a 2" tube through a cone. The 2" tube houses the baffle. The baffle is held captive by the end component, another 2" mandrel bend section. To make the muffler re-packable, as well as to add future possibilities of changing the outlet (vertical pipe, different elbow, etc.), the end has a pair of V-band rings and V-band clamp. The pipe components came from Cone Engineering, the baffle is from Cycle Shack, and the V-band parts were from siliconeintakes.com.
I can't take credit for the welds. Where I work, we build fire apparatus, we have some of the best people TIG welding stainless pipe in the industry. I left it to a seasoned pro.
Here's the assembly components:
Here's a partial assembly (minus the packing for clarity):
Here's the full assembly:
Left side:
Right side: