Had a 67 GTO vert (GM A body) - that was still body on frame and it had a beefier frame as well. Have yet to install it but with my 68 vert I'm doing the USCarTool stiffening kit (minus the torque boxes as verts already have those). I HATE cowl shake. My Goat and my first fish vert (68340S) had cowl shake and going over rough roads or railroad tracks - always kinda' freaked me out. Swore If I had another vert I'd do everything I could to eliminate it.