A-Body Frame/Body Jig

A question I have for all the "former drips under pressure" is how much frame rail/body twist is tolerable for an a-body street car. My 67 Barracuda vert was tagged pretty good in the passenger side before I inherited it. I had the frame "straightened" at a shop, but I notice that when I have it up on jacks, completely gutted (no engine, transmission, k-frame or interior, that the drivers side frame rail is off the jack by about 1/2 inch. Doors, trunk and hood open and close fine, but before I weld in frame connectors I want to know if further adjustment is needed.