Reds got a good point and you say your on your second one that "seemed to work"... probably one of the easiest source of the problem to eliminate as well.
I'm no expert just past experience to go on which is why I say electrical, I don't think it's dizzy related unless its a cracked cap, I'd be looking at the coil or ballast after the fuel pump proved good, then the float... that way it will be in the last place you look
