Although I have not installed either Pioneer DMH you and subfixer referred to, having installed 3 Pioneers double din units with CD and DVD players, as long as front panel doesn?t have to flip open (as with DMHs), you should be able to install the unit behind the bezel opening with minor mod to mounting adapters.
And, I agree OEM Bose set up is hard to beat with non-OEM amp and speakers due to lack of room up front.
One trick is to replace 50 w C4 corvette Bose ams with 100 w Bose amps used in mid 90s Cadillacs. This allows a bit more oomph to the system.
https://www.zr1.net/forum/showthread...ight=Subwoofer
Adding a low profile sub hooked up to a dedicated amp for subwoofer only can be done and adds missing base to the sound but it a whole new subject.