With the engine at idle, you shouldn't see any fuel going down the carb, or at the most, a very light spray mist. If you have drips or heavy spry, you are over fueling. With 3 and 4 cylinders wet, it sure sounds like a carb problem since those two holes are the first to receive fuel.
Checking the valves can be done a number of ways, I like to turn the engine till both valves are off the cam (closed) on the first cylinder. I set the to the proper spec then turn the engine so the next cylinder has closed valves, an so on till all six are done. I find it easier for me and I know each one was done the way it should be. I do end up turning the engine more times, put I'm OK with that.
Don't get hung up on the timing marks, just set it where it runs the best till you can get the whole package working together.
While the carb is off soaking in cleaner, recheck the valves. Also check the hold down bolts on the intake to head and intake to exhaust manifold. Plug off all vacuum lines except to the vacuum advance. Check the vacuum advance for a leak, suck on the hose and see if it holds vacuum.
You need to eliminate all possible reason for a leak or problem before moving forward.
Joe
