Hi Andy!
Indeed a very lucky chap..as RBG says, you'll need a braze on front mech for the RC100 frameset, I'm currently running a Mavic, but Suntour, Shimano and Campagnolo also did them, depending what spec you're going to build it up with.
The RC100 also came with Bullseye cranks, you'd have to get the BB with it too however, which are usually knocking around ebay.
The stem maybe a problem as it was a special Pace version which clamped into the forks, Gil M may be able to advise if not Justbackdated.
Don't worry too much about the Magura cable guide, zips are perfectly fine...
Let us know how the build goes, and pop you bike on my website...great story mate!!!
Rich