Hi just got a project formula .and I figure I will be a couple of years before I splash her . Now she has not been in the water since 07 . My question is what should I do with the tank . Should I flush it out and put some fresh gas in it with stable or let it evaporate and leave it dry

Pump out what you can now and leave it mostly dry. Worry about flushing and new fuel when it gets closer to splash time.