Thanks for all of the compliments!
CH, I did use a wide crank. This bike was originally built with a HS kit. I installed the wide crank and 3 piece adaptor then. After adding this engine, I chose to leave them. They are more comfortable to me than regular pedals. Besides, they aren't really for using now. More for footrests than anything else.
My engine is a little off the bottom tube. When I first built this bike with the HS kit, I went through great lengths to build an anti-vibration engine mount. It turned out that the tubing I had already welded into the frame was the perfect height for this engine to let the pedal chain clear without any modification and the starter on top of the engine would clear the frame. The only modification I needed to make was the intake. In all honesty, it was easier for me to fab up an intake than redo everything else that would be needed. Kind of the lazy way out, maybe, but I really wanted my pedal chain to look normal for some reason.
The jackshaft had absolutely no plan at all other than I knew I needed one. I could either mount the engine off center with no jackshaft or center with jackshaft. Centered engine and more gearing options seemed like a no brainer. When the parts came in, I took them out to the shop, looked at the bike while I smoked a cig, then started welding. That was about the extent of the plan. Ordering the parts. The free wheeling sprocket and heavy duty hub assembly were already being used on the previous build and I wanted to keep all of it. I didn't want to add more gears to the pedal side on this one.
Here is a pic of the very first install on the bike. I later added the anti-vibration mount.
Yeah, that's my wife in the back ground. Her legs are sexier than the bike and I think she knows it. Dang short shorts always make me forget something!