On my 1999 it is in a box mounted on the firewall. Open the hood and look to the upper right.
Edit: Just noticed that your MH is the DP not the Gasser. I had an issue with my disconnect switch where I had to hit the switch 3 or 4 times before it would reconnect. Ended up replacing the solenoid. Won't help you find the solenoid, but might get you 12V power for the short term.
For the long term, check out Newgle (
link). You register your MH serial and it gives you access to any documentation that Newmar still has for your MH. Bad part is, it takes like 3 days for Newmar to send you your login.