Others will chime in with expert advice, but here is what I have learned in the last week or so.
The Echlin from Napa has had a lot of problems. That is too bad, because I like Napa.
The best sending unit is from Ford itself, and may be difficult to find. The second best is a Borg Warner, and I had been given a hint to go down to O'reilly Auto parts chain, and check out their sending unit. I was able to buy a Borg Warner in an O'reillys box for very cheap, with no waiting.
I do not know the part numbers.
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