Try this:

AIRTEX Part # 5S1537
**Non-stock item--shipping delayed up to 2 business days**
$30.79

http://www.rockauto.com/catalog/x,carcode,1177051,parttype,2188

http://info.rockauto.com/Airtex/Detail.html?5S1537.jpg

BTW the temp gage on my old 2.8 Troop never read much above 1/4 anyway, except for when it overheated after blowing a heater core hose and it read almost 1/2!!

My 3.4 will read just a bit higher than 1/4 but not much. I don't think Isuzu calibrated their temp gage very accurately to the GM-style sending unit in the cyl head.

You can check the entire gage ckt by grounding the wire that connects to the temp sender, then turning the ign on (or maybe it needs to be running, I forget!); you should get full-scale deflection on the temp gage.

HTH...........ed

P.S. looks like you'll have to copy and paste that first link into your address bar, it didn't linky-fy very well.