@Alan Maurer When I was dealing with this GeeBee's thread was super helpful. Doesn't sound like you need to address anything more than the strobe light switch, but you can see what both GeeBee and I (mine is similar) saw in the headliner with removing the EL panel. Strobe was attached to the plate..but the split landing and taxi lights were separate.
https://mooneyspace.com/topic/45953-long-body-overhead-light-panel-install-update/
From link above: My light panel for the overhead had become warped and the backlighting was not working. A little investigation revealed it was an electro-luminescent panel powered by an AC inverter in the overhead. I checked the inverter power output and it was good. Further investigation revealed several interesting facts.
1. The life span of these panels is about 2000 hours and since the panel is continuous power, if the airplane has more than 2000 hours, the panel is near EOL.
2. The inverter is simply glued in the overhead with RTV
3. There are two type of switches and panels. The MM makes mention of only the newer panel where all switch/breakers except the landing and taxi light switches snap into and are retained by the EL panel. (The taxi and landing lights are simple switches with CBs on the main electrical panel) The older type panels have the switch/breakers mounted on an aluminum plate and the EL panel is attached to the aluminum panel. Here is a picture. As you can see my panel is warped which occurs at EOL due to excessive heat build up from the AC power. You can also see the cutout in the aluminum panel to allow the landing and taxi light switches which are retained by screws in the overhead.
Also for reference:
Screws for overhead panel:
PS6C8DL01BK
MS35206-230 6-32 thread ½”
MS35214-27 6-32 thread ½” black brass
INVERTER: The inverter is located in the overhead headliner very close to the EL panel (2 to 3 inches away). As I recall I had to drop the headliner to access the inverter. From my notes (2008, my how time flies) the inverter is LP105A in the parts manual and is an ERG LPS28-3-3P. I have attached the specs below. It is probably a commercially available part but I just ordered both parts from Dan at LASAR for convenience. I believe the inverter was about $100.00.
It is fairly easy to check the inverter. From the spec sheet for the part number an LPS28-3-3P will take in 28VDC and output 120 Vms. A DMM on the AC scale will show if you have voltage on the pins on the connector. If you have voltage but no light the inverter is good and the panel is bad. Something less than 120 AC will cause the panel to be dim.
At the time I repaired my EL panel, I ordered a back up inverter from ERG and they mentioned it was obsolete and no longer produced...they had 3 pieces at the time and Lasar also seemed to have some. Not sure if this is still the case.