If memory serves correct, after the disastrous 1972(?) NHRA Pro Stock season, Chrysler figure if a "360 degree roll cage" is legal, why not slice the drip rails ? They sent one factory car to tech & Chevrolet, I mean NHRA, failed it.I've done some searching, not seeing much on this subject. Doesn't seem like it's been done on a mopar. Find that hard to believe.