Hello and welcome to the family bro. I also had to do some work to my ninjette to get her running the first time I got her, I'll forever cherish how she roared to life after reassembling her (following carb cleaning and a LOT of maintenance). Kudos to you for doing the work.
On a related note, I don't foresee myself ever having a problem with the gas cap seeing as I have this baby
Ride and stay safe man.