Awesome that your sons are interested.
My nephews were interested, even told one that if he came over and worked on a 340 car, he could have it when he was ready to drive.... They got poisoned by their father that all old cars are junk and you don't want to bother with that stuff... Coming from a guy that has a hard time figuring out which end of a screwdriver to hold! :)
Keep at it, you're doing nice work.