Abe, Westach do a Universal Temperature Gauge for $65 and a Dipstick Sensor for $19. I got mine from Geno's Garage at http://22.214.171.124/CoastalData/show...ectGroup_ID=97
Geno's also sell a variety of mounting plates. You need a power supply, and I took mine from the back of the cigar lighting socket. You can use the dipstick sensor as designed, and tie it to the end of the transmission dipstick, but this will only give you the temperature in the pan, after the fluid has been through the cooler. It's better to take the temperature of the fluid as it emerges from the transmission, before the cooler. I taped my sensor to the output line from the transmission. I cleaned up the line with wire wool, and smeared heat sink compound (from Radio Shack) in between the line and sensor, and wrapped the whole assembly in self-amalgamating tape. This has worked without any problem for two years, and it's very responsive. Your vehicle may already have a port for a transmission temperature sensor, so the above may not be necessary for you. I try to keep below 200 degrees, but this is easily exceeded when backing into a campsite, or stop-start at multiple stop lights when towing the Airstream. If you're not confident with a soldering iron and vehicle electrics, I suggest you buy the parts, and give the installation job to a shop. Good luck. Nick.