using (the right stuff) metal conditioner on bare metal. do i use seam seal right over that? or prime first? before appling seamseal. its for engine compartment, trunk, floor pan, & underside of 66 mustang coupe. all the places not seen so much on the car. and fender wells. im not doing the body paint, i'll leave that to the pro's.

 

Moved to the correct tech section.....classics might be the best spot for this.....

 

All the parts we have pulled off or replaced the seam sealer on.. they had the black paint or primer under the seam sealer. I know you can paint over the seam sealer. But with all the rust I found under the sealer, I don't think I would leave the metal unprotected under it. (we pulled up seam sealer in the trunk, around the wheel housings, the area looked fine, just cracked or lifted seam sealer. But after removing the sealer, we found the welds to be rusted from the seam sealer side (not rusted through). It was shocking since we thought the area was free of rust! The welds (without rust) were painted black under the black seam sealer so I think that is how it came from the factory..)
Others may know the exact procedure, but this is what it looks like. Hope this helped.