You can download a copy of your owner's manual here:
https://www.monacocoach.com/rv-owners-manuals
I noticed it skips the 2003 model. I would download both the 2002 and 2004 and compare them.
Monaco used similar light fixtures in many of their coaches.
If you could post a picture, maybe we can guide you through the repair. I usually take the picture with my phone and email it to myself. Then I save it to my computer pictures folder.
Click on the "Go Advanced" button below your Quick Reply window and upload the picture from your computer.