I have an 18' Appalachian tandem with a full metal deck about 1800 lbs. Randy Roverover weighed his Disco 1 and if I recall it was over 5000#., and ours are set up the same.
But I'm considering an aluminum trailer for utility work, hauling the Kubota etc.
Fitted the brake controller with the bracket slightly behind the OBD2 connector. It blocks access to the connector, but it's not hard to move it. Not difficult to reach down to adjust the sensitivity knob, the display requires a tilt of the head. In 25 years of towing a variety of trailers, I have never had to manually apply the trailer brakes in a panic, so I think it'll work for me.
I also mounted a 3 D cell maglite to the access panel for the NAV. Clips hold the panel well, and the light clips also hold firmly.
And a pic of the tow ball height for my 18' trailer. Drove it with an 88" S3 from the body shop, w/o the brakes fitted and was aware of the weight, but handle it just fine.