Anytime I work on a bike that hasn't run in awhile, I install a disposable fuel filter between the petcock and the carbs. It is also a great diagnostic tool since you can glance at it and see if you're flowing fuel or not. Little ones like this are designed for lawn mowers and work great since they don't require much space.
Can we place bets one if it will run and how much oil/ smoke it will blow? I got beer on it that it smokes like your keeping bee's with it if it runs.