Is the thick insulator base gasket still in place? Have you checked to see if the valve in your passenger side exhaust manifold may be stuck in a restrictive position causing your intake to run hot and boil fuel as you suggested? Another old school trick is to rev it up and hold the choke closed a few times and see if that unclogs any air bleeds that might be causing a siphon. If it is draining into your manifold your oil will start smelling like fuel very soon. Is the mechanical pump still connected in series?