Fun and games continued.

[Russell E Johnson]

The dreaded hafta--yep, I stole Tina's accurate expression--has got me too. The entire ceiling to the rear of the AC unit is all rotted out. I now hafta pull the other cabinets down. Where the antenna is located I ran into the dreaded black compost wood. I have removed all the insulation and wood all the way to the fiberglass of the roof. That antenna has probably been leaking since the day it was installed.
There are 1"x1.5" metal tube crossbeams on each end of the the AC unit. The one that is up front, and adjacent to the antenna, is completely rusted out. So I will be replacing that one and probably will replace the one at the rear of the AC unit as it has been doing all the supporting of the AC unit and roof all these years. It is rusted also from the leeching water and is probably bent and weak.
I am going to remove the obsolete antenna completely and fiberglass over the hole in the roof (something I tried to get a reputable--pfft--RV garage to do but they refused and said that it was better to leave it). When I am done I will know for sure that it will not leak there again.
One positive note to this development, there are no screws coming from the top down holding the cabinet up on the passenger side. So hopefully that will be the case when I pull down the one on the driver's side tomorrow. Then finish gutting the rest of the ceiling material all the way to the fiberglass.
Another positive note is that all the material I have removed thus far is dry. All the rain has not found an entrance into the MMP. YEA!!!! Enjoy the pictures of today's mess.

[Tina]

So sorry to see that!  Isn't it weird, at first glance that composted black wood makes it look like the thing went through a fire.  That's the first thing my mom said when she saw some of mine, that there must have been a fire. Then I put some good black "dirt" in her hand. LOL

Good that you have no screws to deal with.

Those danged old antennas are the devils work....I'm just sure of it.  I believe it is 80% cause of the leak issues on mine. I'll be doing the same as you, it's going away and the hole will be properly sealed.

Following along here is going to be a learning experience, I'm sure.

I'll be a cheerleader!  Go forward young man...you CAN DOOEEET!  :)