Well after some research online and input from this group I went ahead and bought a temp gauge/trans for my 2004 GMC x-cab 1500. Gauge came from
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nice gauge works great! And bought a single gauge pillar pod to mount it in. Well the big question before starting this project was where/how to install the sensor.....I found a factory thread test hole plug on the drivers side of the trans. just above the pan.A little hard to see/find with the linkage in the way.But the plug came out and the sensor threaded right in no problem.(tape on threads)= no leaks :) Anyway then ran the wires in the wire wall and up to the pillar after hook in to the fuse box.Couple wire ties on the way to keep the wire out of harms way (hot pipes).Took it for it's first run this weekend pulling my 32' Zinger travel tr. Went up I91 in VT to exit 8 (lots of steep hills) Temp ran on the hard pull areas from 190-197 F .
Keith