I'm not sure if the colors are different between Cuda's and Challengers -- and I hate to offer something different from MEK who knows a lot more than I -- but I've re-done both my white interiors in my '70 and '74 (the '74 is very original) and the SEM #103 Super White was a perfect match. Again - perhaps the Cuda's are different. I agree with the Landeau Black and preparation of the surface is very important.
VT Mopar