1977 kz900 restoration

Would like to get an opinion from everyone on just how much they think this would be worth if it's running and cleaned up pretty well and the chrome is polished. its got about 31k miles on it. 3rd owner. the previous owner let it sit for 6 year WITH gas in the tank and carbs...sad. However, my dad and I have cleaned the carbs and built an auxiliary tank to test the engine for now. in about 30m from now we are going to try and fire it up for the first time. if it fires up we know its worth putting more time into restoring the gas tank. Interested in hearing any thoughts, advice, tips or tricks. thanks

Fired the bike up!! its running pretty well. had a little issue with the idling w/o choke at first but messed with the idle needle and now it's idling with the choke off. still trying to bring down the idle rpms a little the mixture screws are setback to 1.5. it idles between 1500-1750rpm. we haven't synced the carbs which is an option, but considering if it really needs it at this point. Also, another issue I forgot to mention is the shifting. the trans will not go past neutral. after having the bike running for a bit we tried it but it wasn't giving. thought it might take a little movement to get it to shift so we will try that. any input there? i've read it could be the forks? the clutch feels good. maybe the plates are stuck together and just needs a little extra force?

Bike has to be moving (back wheel turning ) in order for it to shift up past neutral. It is part of the Kawasaki neutral finder system.