Damn it!!! I screwed up the 80 the first day I got it!!

[SheeBan420]

Alright so I bought a 94 YZ 80 for a friend of mine for $250. The only catch was that I had to go pick it up at his cabin up north. So the day I got there was a saturday morning and I had just drove all night after working the night before and I was ready to do some 80 ridin. well it didn't really wanna start so I put a new plug in it and tried again. finally got it to start but it wasn't running very good at all so I shut it off and started looking around. Well I found out that a mouse took over my air box and built a nest and ate a hole in my air filter. well I cleaned it all up, took the carb apart and check everywere that could have been cloged with mouse shit. but it was still running like shit. Finaly when I got the bike home I checked the compression and only had 30psi. When I took the cylinder off there was a nice groove down the side of the cylinder wall. So I just took the cylinder in to get re-plated, ($255) bought a new piston and ring, ($47 on ebay) and gasket kit. ($20) So once I get all parts in im putting it back together and im gonna ride the shit out of it. I only have one question for all you dirt bike guys, What should I have my air and fuel screw set at?? I just wanna make sure after all of this bullshit that this little bike will be running good. any one got any ideas? it is a stock 1994 YZ 80 with a FMF pipe and a 300 main jet. (300 seems big to me but before I fucked it up that bike ran really good.)