You can us a plug location on the transmission for the temp sensor. I did this until I added the line with the T built into it.

 

I thought about this, but I read that a lot of people have seen dramatic differences between using the "test" port on the transmission and installing a probe on the hot line. A lot of people have stated that the test port is more for pressure testing, and that it is less responsive because it really measures the temperature of the transmission case rather than the fluid. I think i'll grab the fitting from Diesel Manor, but if the port on the transmission is working for you, i'd say go for it. Thanks for the PDF, it helped me get a better idea of what i'm looking at down there.

 

I used this test port on my stock tran for almost 2 years. When I installed the billet DTT I moved it to the hot line per the recomendation of Scott Hovey who built/installed the DTT.