tranny cooler placement

I am installing a tranny cooler and noticed there is a sensor of some sort in front of the condensor radiator. Does anyone know what this sensor is and what is the best area for placement of the tranny cooler? Thank you

The sensor is the ambient air temp. sensor for the AC.

I found a B&M style 24,000 11x11x3/4" Cooler kit and put it right in front of the rad. I didn't ever have to drill any holes. Granted, I'm in Canada and found it at Canadian Tire but it had all of the brackets and hoses so I took off the bracket in front of the hood latch and mounted it under those bolts and bypassed the cooler in the rad completely. I did put bolts in the empty holes so nothing would leak out. It only took about 30min and cost less than $100. Good luck