Important Restoration Dilemma Please Help

the only rust that I can see that is forming is right at the cat whiskers at the top of the doors and a little in the typical spot at the bottom drain below the quarter window, the body work and paint job on the Dart was done probably 5 years ago.... It's just the clear coat that is coming off. No the dart has the regular LBP 7 1/4" under it. the 8 3/4" under the duster is LBP as well. I believe it came from a 68 or 69 Charger. I will have to buy a new set of wheels with different back spacing for the back since it makes the wheels stick out further than the 7 1/4". I'll get the same size so I can keep the same tire for it.