I have a 1989 Mazda 323, when cold engine idles very high, when very cold it idles so high that rev limiter kicks in, and it revs up, limiter kicks in, revs up limiter kicks in, once it warms up idle drops down, but never completely to normal idle

This sounds like something I remember, I would look into my throttle position sensor.. it's supposed to kick it up but only to around 1500 Roma until it warms up and drop it back down to 750 rpms

Have it looked at by a dealer,iam not sure here but i think you have a vacumn leak like the feed pipe to the servo split but really you need a mechanic who works on these cars day in day out and they will go straight too the problem for you