Found problem and have made repairs. Disassembled and found both coupler mounting pads slightly bent upwards which I corrected. Still buck toothed. Filed down all flash and front and rear corners. Still buck toothed. Found shell and frame mismatched. Frame too long for shell. Filed about 1/64 off front face of coupler mounts. That did it. Plastic shell was not curled or otherwise damaged. It was factory problem. I think Atlas used old production shell atop new drive and frame. Other modelers likely to encounter same issue. Models are Atlas Classic, made in China. SSW black widow--beauties. Thanks for your interest in helping me.
Croehl,Can you sahre a picture?Atlas usually uses pretty fine scale moulding on their newer items, you may be able to use hot Tap Water from the kitchen faucet to assist in manually trying to bend them back.Without seeing it, it is hard to make a better suggestion, as some may be to extreme, & damage the parts.