Thanks everyone for the input.
I do know the firewall slanted towards the back at the top. I have read as much info as I can find about the front drive components. The goal is to start the engine before it goes into the car. At this point the engine is all together except for the timing cover, front drive components and induction. The engine is an all aluminum 9.2 inch deck Clevor built around the Ford M-6010-Z35192 block (basically a Windsor with Cleveland journals) and Edelbrock Clevor heads. There are a couple of serpentine drive systems that look reasonably compact that might bolt onto the engine. Since I haven't purchased a timing cover yet, going with a short reverse rotation water pump and appropriate cover is still an option. At cylinder head height there needs to be about 6 inches between the front of the cylinder head to the firewall at that height. If a distributor cap barely has clearance then it seems unlikely this front drive assembly will fit.
I have purchased a few items from IPSCO. They do very nice work. I forgot about that custom bracket. That looks like a good option. I will have to ask Mark if it bolts up to a Windsor block and the pulleys line up. Does that allow for a flat bulkhead cover?