Getting aftermarket carpet really sucks unless you've done it before. Alot of fitting/cutting issues will be had.

I don't know about S14 carpet in S13. I've never really taken a look at S14 carpet to see. But I do know the S14 carpet is crap. The best carpet to get is SOHC carpet. Darker and more rugged than the plush DOHC S13 carpet.

I've been looking around for SOHC carpet, probably just will end up going to a junkyard and getting it there. Give it a nice shampoo and pressure wash, mend the holes for the auto belts, and it'll be good to go.