Newman's 1986 BMW 326rb build thread.

You strip the chassis and dip it in a bath of acid, stripping all body insulation, sound deadening, sealant, paint, etc off of the metal, leaving you with nothing but a bare metal shell to work from. It usually sheds some serious weight, too. Its usually done on projects like this where you might want to think about throwing the chassis on a rotisserie and seam welding the chassis, building the cage, etc.