Have a 1989 Ford country Squire have been looking for fuel sending unit can't find one have new tank, new fuel pump everything else needed to revive the car just can't find a sending unit
That's interesting. I can find new fuel tanks and new fuel tank lock rings for your car, but the same vendor (Rockauto) does not show availability of sending units. There are services that rebuild these. Do you have the broken one? If so, you might see about getting it rebuilt. If rebuilding is not an option, you're most likely going to have to find a good used one from a junkyard car or perhaps an NOS or used unit on ebay.
Can you clean up / rebuild the old one? I've been running into similar issues with my fuel tank upgrade. Bought a used tank from a newer car, but can't find the locking ring and sending unit for sale anywhere. Lots of shortages of random parts...
Yeah, you'll need to find a good tank complete with sending unit, pump unit, and everything else. An alternative would be to source a '90s Aero Panther sedan tank and convert your wagon to use it. I always hated that Ford had to separate the fuel pickup/pump and sender until the early '90s when they were combined.
But, the sedan and wagon share the same part, so used or new, look at Town Car up to '89, see if that change will get you what you need.