557 and only able to run 18* of initial, that really weak. It's only got 170 cranking pressure. Not earth shattering

I'd take a jumper cable, hook it to the neg battery and straight to the engine block. See if it starts easier. If so you found a grounding issue.

If it's not some crazy compression, doesn't appear to be, that should be above 20* timing and easily spin over.

Lots fo times those bigger cams never give you a really clean idle profile, but, you can get it better than fouling plugs. I have a 340 with stock compression and a 508 camshaft with it locked out at 36*. Starts fine even when warm out here in the desert.