Paul,
Racer Parts Wholesale has the Fuel Safe one. Not sure if that is the one I have, but it works the same. You have to supply the Ohms, and they will ship it. I have a Stewart Warner gauge and it works very nicely. My car isn't at home right now or I would send some pics. It should be here in the next day or two. Exhaust is being fabed at present.The unit can be shortened to 3 1/2" if need be. Mine has the same features as theirs I believe. It should have a low level sensor that is adjustable and can be wired to turn on a warning light. If it doesn't then mine is different and I will send you the info when the car gets home. The full point is adjustable as well. Not exactly cheap, but it is nice to have a reminder that the tank is getting low. If this isn't the page just scroll down near the end of the catalog.
http://www.racerpartswholesale.com/d...%20Catalog.pdf