Dude sometimes a car like this is not even worth working on anymore. Sounds like whoever did work before you was not a tech but a wanna be tech and now it sounds like you're married to the car. I feel your pain and I wish you luck man. I think personally with the way this car is a sealant won't work and the only way to go is taking the propper steps. That's just me, sometimes the best way is the hardest way.