Mike - the distributor is about 3.900/3.915 (about as good as I can measure without pulling the hood). There is also a taper on the bottom ~1/4 of the upper body that goes down to about 3.5. It also stands proud of the block about 3.5 inches.

I use the PCV at the front of the engine to get it away from return oil flow and the fact that the carb has the fitting at the front - also just because I can.

Yes, that is the Speedway 6" fuel filter at the back. I used 2" billet clamps from Yearwood and a home made bracket. I plan on putting a SS hard line instead of the braided over the winter so that location may end up changing.

Randy - Thanks. I really appreciate the good words