Haha not long at all. Have you though about shaving the clock slot so you can fit the controller in it rather than behind it? I had my turbo timer in there (Profec B is above the UHF next to the steering wheel) but they're the same size.
hey nice job that is exactly where i have mine mounted, the difference between us is i grabbed a file and went to work, i squared out the corners and pulled mine through to "FLUSH" mount it with the plastic DIN cover, makes it easier to see and access the buttons and nob.
i would file it square but i hate going to town on something that i don't have a spare of, i use the factory clock mount holes so if it comes down to it the clock can go back in.