Re:
Will double check the downtube, but from memory it's oval.
Most of the groupset is original from what I can tell. DX with XT rear mech. Just had new bb, brake pads, chain, cassette, and cables. Wheels are DX hubs on Araya RM17 rims.
Had to find new forks and stem, which are 92 model year I think. Paint on everything is tatty and again mostly original. Everything works perfectly - I built it up to work with the intention of getting it sprayed and decaled up in future (and finding a decent seat post) but now moving house and need to downsize the stable.