Exhaust leak help

Not sure where the leak is. If it's a gasket you could probably live with it for a while but it could leak fumes into the passenger compartment.

By the way, those are exhaust manifolds on your engine. There have been several threads about what types of better flowing factory manifolds will, or will not, fit in the confines of the narrow 66 & earlier A body engine compartment. I can tell you that headers for the early A can be an expensive proposition. You basically have 3 choices of under chassis headers. Doug's, Spitfires (if you can get them) and TTI's.