Hi
When I import a large JT file i to maya, the maya file becomes like 12 GB.
I cut be a good ideer, if the import, cut with Instance. So if a screw is listed more then one time in the part list, then it will make a copy instance for the rest of the screws in the part list. You may also have to make a tool that finds the Master ''screw'' if you have to change it.
Best regards
Kent Hansen