Looks good man!

I'd say, if you want to get rid of the wires in there, you could use felt or very small black mesh (probably the best of the two). Cut it the same as the bezel and slap it behind. Air will still go through, but you won't see anything (or at least less than presently).

Personally, I'd use those two side slits as warning LED lights (warning for boost/O2 or even a shift light if need be). Would take some work, but it would look like it's suppose to be there, be functional and look great overall with the gauges.

PS don't keep the TB....or Batman will hunt you down!