Last summer, I had to replace an interior lamphouse fan on one of my 35mm screens, knowing that it was probably the last year the lamphouse would be in service for my theatre. The replacement of the fan cost more than what I got for selling the entire lamphouse to another theatre operator this spring.
There will still be a large number of 35mm screens in operation through the next two years, so holding on to the equipment for parts value isn't completely hopeless. It's just a matter of how much trouble you want to go through to move and store the equipment, and find a buyer.
Incidentally, I still have three Century heads available for anyone interested, as well as two Kneisley II lamphouses, a very nice Isco Ultra-Star anamorphic lens, four proximity cue detectors, four Kelmar red readers with power supply, and several guillotine splicers. You might also be surprised what people might pay for them on eBay or Craigslist as collectors items.
Rick