Transmission cooler under driver area? Pass or Proceed?

That unit looks pretty small — did you consider inside the front wheel well, behind the headlight bucket? There is a lot of depth there, and it would be better protected from road damage. I know I have been on road trips that would have ground that thing flat in the position you are showing it (high crown rough roads).
It moves 500 cfm. It should be ok. I am not racing the car except a few test and tunes. I did a mock up and moved the brake line up so I got more clearance than before. I happen to have 2 lengths of -6an line that fit will fit it perfectly so it will go there for the time being. I just ordered some 1/8 npt to -6an fittings so the install will be clean.

Remote Mount : 15 Row Atomic Cool Plate & Fin Remote Transmission Cooler Kit, -8AN


Only thing I’d worry about is getting it too close to the floor. You need enough space (plenum) on both sides of the radiator so air will flow and if it’s flush to the the floor you’ll be p’ing in the wind IMO.
It is set off the floor by the base. There is 1/2-3/4 inch clearance. It is designed not to be flush preventing air flow. I may install a temp gauge as well, not sure about that just yet.