I vote against 426John's advice of firing it up before you diagnose what the problem really is. If there is a plugged oil passage or that #4 cam bearing isn't right, you're going to cause your poopy situation to get worse and way more expensive to fix. It worked out for that guy but that is pretty damn lucky in my opinion.

I hate to beat a dead horse, but have you tried priming while someone turns the engine over? Everyone is suggesting it but I can't tell if you've actually tried it yet.

Is the oil pump new? You seem to say it doesn't load the drill while priming it. Did the gasket line up right and not block any passages in the oil pump? I guess I'm confused on that one becuase you say it's priming the one side of the engine ok.