OK, you have my attention.
Do you do custom loco shells for steam locomotives to fit frames that are out-of-production? I am thinking about some distinctive but never-to-be-commercially-produced B&O locomotives like the S1a, T3b and P1d, which could be fit on frames from Con-Cor and Bachmann and others that have correct wheel arrangements and wheel sizes. The trick is to make the boilers and cabs the correct shapes, and make those fit the chosen mechanisms. I would like those major parts to be produced "bare", so that they would be easier to finish and then detail, rather than to try to print on the domes, pipes and other smaller detailed parts. Perhaps some of the detailed parts could be printed separately, such as unusual steam and sand domes, double stacks, etc.
I have drawings of various sorts for each of those locomotives, but do not know whether they are adequate for your needs.