This was modeled in Google SketchUp free version, so no STEP export. Sorry. I took measurements from my machine without disassembling it, so accuracy is probably in the +/- 1mm range in places. This might be adequate for what you have in mind, but it was mainly intended as a visual reference for potential customers, to aid assembly and for attachment/mod mock-ups. I'm reluctant to share the model file since it could be mistaken, down the line, as being official and accurate when it's neither. I'd just hate to mislead anyone and have them machine replacement parts from it that don't quite fit. Otherwise I'm all for sharing, such as it is.