Are you lucky!
I have a NOS XTR, 31.8, down pull front derailleur from the mid-90's (FD-M900). The arc of the cage exactly matches a 52t chainring so I can't think of any reason why it wouldn't work for you.
PM me if you're interested. I'd be willing to let that go real cheap or even trade for something like old style Ultegra SPD pedals. What've you got for tradeing stock?