Usually compiled files are uploaded under Releases tab along with a zip of the sources from which these are compiled out. This way only "real" source files (for main project, tests, samples) are kept under version control in the repository.
In VB6 case probably compatibility targets must be kept in the repository too for the source to be able to be opened in VBIDE, probably these will need versioning too.
I tried to use .tlb files for compatibility but these can be used only for Project compatibility targets. Binary compatibility needs a compiled VB6 binary as target.
Just my $.02