You can buy aftermarket tranny lines that have the fitting for a temp sensor in it, but they are a decent chunk of change.

Bring it to a mechanic and get him to cut the line, put a T in the line, and then put it all back together with a flaring tool.

It's not hard. Just go with the logical option.

 

Instead of cutting the cooling line dieselmanor makes a line that is already T for ya http://www.dieselmanor.com/dm_products/DM-CLG3.asp just a thought, and their nothing wrong with splicing a T in their jst like geezir said

 

There's the link..couldn't find it either.

But that proves my point. $134 (plus shipping) for a line with a T installed...or a couple bucks for a mechanic to install the T for you. It's going to be the exact same setup either way.

 

keep it stock, that aint hard, but whats the fun in that, I would go in the pan, because then you know what is going on live right there. but the hot side line is the second best option, I wouldnt go and start pulling plugs out the side of your tranny either.

 

In the hot line is the best place to have it. Pan has a mixture of hot and cooled oil in it so you aren't getting a true reading of the oil. In the hot line will tell you 100% if you've cooked your oil or are getting close.