Experience comes from mistakes. Knowledge comes from experience. In order to have the latter, you must have lived through the mistakes.
I noticed someone mentioned a Briggs engine, I had a similar experience with a rebuild on an amost brand new engine. The result was a blown motor. "litarally, I got it to run for about 1 minute (like crap) and then I had a hole in the engine case."
You have more guts than most taking on the rebuild that you are working on (when you get the manual, your going to sa stuff like "Damn, I should have known that" and "That is a whole lot easier than the way I did it!")
Be patient and wait for the manual. It has specs and stuff that you really need to make your scoot the performance monster that you want it to be.