Congratulations on the purchase, i'm a wee bit jealous though as i had a 16" Zaskar before and loved it, bought it new in about 95 will get another someday.
Best metal polish i've used is Autosol, Halfords sell it so it may well be the stuff you have used already.
Forks should be ok but you may be better with 60mm, i'm sure standard Judys are around 60mm anyway or what about a set of Manitou 4's ?
How you do the build is up to you, if you plan to use the bike regular a few modern bits is ok, i'd still try and use five bolt cranks and a square taper BB though but modern rims, tyres and seat probably wont be frowned on too much, whatever you do dont fit riser bars and bar ends
I've found mid 90's stuff fairly easy to find if you are doing a period build, since i've joined this site i've bought a couple of sets of XT V brakes and mechs in pretty mint condition also seen loads of mechs and shifters for sale for reasonable money.
Syncro's or Controltech post, bars and stem will work well, as the frame is polished i'd go for black for these but go for silver cranks and rings and probably wheel rims, having everything black will make it look modern and heavy so it needs to be a mix really.