The UNKNOWN fuel sending unit

[Cartoonface]

Howdy all!
I have a 1972 K5 Blazer....with a unique fuel tank installed by the original owner back in '78.
Here it is on the ground, you're looking at the top of it:


The problem I am having is finding a replacement Fuel Sending unit.


I need 90 Ohms and any length can be made to fit ( tank is 14" deep where it mounts)

If I have to I can live with just a sending unit and pick-up fuel somewhere else.

The closest I've found is a Spectra Premium FG142A...but it's only 30 ohms.

Any ideas where I can find what I need without modifying the $79.00 30ohm FG142A ?

Thanks a bunch mates!