This is what my box looks like
https://rvelectronics.visonerv.com/c...M280844/s1.pl?
Might not be the exact match but pretty close.
This only controls the front and rear TV's and VCR, Antenna, Cable, and Satillite. It has nothing to do with the audio equipment int the front cabinet above the driver.
The stereo, DVD, Disc player are wired through a different control.
You can download a manual and brochure from here
https://www.monacocoach.com/service-and-repairs/
They don't list a 2000 manual but have a 2001, which will be very close.
In the brochure it will list the 38 model, look at the length and you'll see it's longer, probably +39' 8", that's what mine is. I have the same chassis.
Look at joining the Monacoers.org site. They have a large database of info and I believe they have a set of wiring diagrams for your coach. The members there will be about as close to experts as you can get.
You have a great coach, good luck.