PB is ok, but try the GM product I posted above next time. I've built many many street rods from the 30s to late 60s, over the past 40+ years, so I've pretty much tried every rust buster ever producedPB blaster is the best I have used so far. 42 yrs in aviation maintenance. just an opinion. And I second the poster that recommended anti sieze compound. recently removed my exhaust manifold, exhaust flange and exhaust riser after 7 yrs of use and abuse. not one bolt or nut failed to come apart. I found no rust on the studs at all. I use permatex by the way.