Slant 6- Idle and Running

I would check the timing chain for excess stretch and distributor shaft for slop. You need to have some kind of timing marks, somehow someway to have something to accurately reference.

Where is the fuel leak at exactly? Is it leaking from a fitting and running down the pump to where it mounts on the block or the from the pump to block connection? If it is leaking internally in the pump (ruptured diaphragm) the fuel will mix with the oil and dilute the oil (not good). Does the oil smell like gas?

Post a couple pictures of the mounted carb and the attached linkages.