Being a newer bike, this doesn't really belong here - but......

A few years old Lemond Reno for $150. Aluminum frame, carbon fork, 9 speed Tiagra group. Everything seems to be in working order except the RD and derailluer hanger. Get this, though - the guy gave me what he swears is the original rear wheel. Trouble is, it has a 6 speed freewheel on a Suntour LePree hub, laced to a 700c UKAI rim. Front wheel matches, so wherever this wheelset came from, the originals appear to have been separated from the bike.

The frame is cosmetically excellent and seems to be sound. First blush is that I need, at minimum, a RD, hanger, and bar tape. I might need a rear wheel, depending on the answers to my questions, below.

Questions:

1) I have several seven speed wheels with cassette hubs. Can I drop a 9 speed cassette on, or is the spacing/dishing different?

2) I have a nice Campy rim laced to a Exage cassette body hub that I picked up at a swap meet. How do I tell what speed cassette it is dished for? It slips into the rear dropouts of this bike, so the axle/hub seems to be the right width.

3) If anyone has a decent 9 speed rear wheel and wants to trade for a 7 speed wheel, drop me a line. I can put together a set, if need be.