I want to hook up a tranny temp guage but am not sure how it's done.

Mark

Depends on whos kit you buy. Most of them have an inline type temp sensor. It goes into the oil cooler return line to measure the temperature of the oil returning to the tranny.

You cut the steel line (top one) and put the sensor fittings in. Then it's just a matter of running the sending unit wire up to the gauge.

First I found a steel bolt that the sender threaded into. Then I took my pan off and drilled a hole on the drivers side just behind where the TCC harness goes into the case. Then I brought it to a welding shop where they TIG welded the bolt to it.

That sounds more like a nut than a bolt to me.

I have the sender for my trans temp gauge in the pan, too. One nice advantage is that you can use it as a drain plug too.

Yeah you know what I meant

The option I chose was to install an external trans filter along with my trans cooler. The filter bracket already has a treaded port for a temp sender.

I also used brass adapter fittngs and plumbed the whole thing with steel braided hose. No cutting any lines or drilling any holes.