I've done this on other forums and it's been pretty successful, so I think it would benefit everyone else. I know S12's aren't exactly common, but auto makers tend to cross over lots of parts which may fit or be made to fit our cars and some times the same part can be found cheaper by referencing it to a different car.
Post the part, what needs to be modified to work, and what it came off.
For example, here are some that I've read on the forum:
S13/14 steering wheels - direct fit
Nissan R200 LSD diffs from Z31's - direct fit to TURBO cars
S13 coilovers - needs S13 front suspension conversion
Feel more than welcome to include write ups, how to's or videos on modifying or installing! I will add to this thread when ever I find something or read about it.
Post Merge
Also, if the mods find that this is better fitted in another area, do what you need to lol.