trans temp gauge

okay so im trying to hook up a temp gauge for my trans and they said something about puttuing the sensor in the trans test port but when i look online to fidn this i cant find anything and to find it thru mitsubishi i gotta subscribe and i gotta pay for something that im only gonna use once. Could anyone tell me where the test port is located on the trans??

Sounds like and electrical connector, never heard of it though.

its a bolt thats somewheres in the area of the trans pan. thansk anyway tho