4EAT Aux Trans Cooler: Need Advice on Temp Gauge

Hey everybody! Ive been on hiatus because my lifes been super crazy hectic but its good to be back! So I finally pulled the trigger and ordered a Hayden bar and plate 677 trans cooler. Ill be running it as an auxillary plumbed in series with my Koyo oem style rad and cooler. I also ordered a towing receiver and Ill be going in for my protune soon so Id like to keep my trans temp in check. Could you give me some advice on where to install the sensor for a trans temp sensor? Ive read one guy spliced a T fitting into the rubber hose after the 2nd cooler and 1 guy used an adapter that replaced His trans drain plug. Someone else suggested an oil filter sandwich adapter with a hole for a sensor.

The last option, the sandwich adapter is what I was thinking would be the most practical but I have no idea what threading the trans filter is so i cant find or order a sandwich adapter plate accordingly. Im pretty certain its the exact same as the engine oil filter but Im not sure if a sandwich plate adapter will work for the trans if the sandwich plates made for an engine oil filter, mainly because of the potential difference in diameter(tight seal and all that).

Im not at all against running a T fitting inline with the rubber cooler hose but I didnt know how solid that would be regarding leaks, though the cooler itself just uses barb fittings and the hose just pushes on. Im looking for something that will be in the most accurate position but also a practical location. 52mm gauge would be preferrable as Ill probably be buying or ,aking a 3 gauge pod for the dash clock location. So I need to not only pick a good gauge that isnt expensive, but the best way to install the sensor itself. As always, thank you all in advance for your help!