https://www.flickr.com/photos/131892445@N08/shares/11DU3q
In my '51 3600, I cut a hole in the transmission cover plate just big enough to accommodate the rectangular top of the T5. It was nearly flush, but protruded just enough to not let the plate sit completely flat. I went to Lowe's and bought a 1ft piece off a roll of floor cushion mat for work stations. It's about half inch thick, rubbery, and basically made a perfect gasket if you will that pinches between that part of the T5 and the plate, sealing it. Taped it down with gorilla tape, and cut a hole just big enough for the "round" shifter arm cover. The boot from the original T5 covers it nicely and with carpet installed, it looks perfect.
