'64 Overlander Shower Wall Material

[riowerks]

We're in the process of renovating a 1964 Overlander. There are about a bazillion holes in the walls that need to be patched, including in the rear shower wall. Unlike the rest of the cabin which is zolatone (or something like that) over aluminum, the shower wall above where the tub goes has a different coating. It's not vinyl, but might be some kind of fiberglass? It's been painted over and the pain is peeling so will have to be stripped.

Does anyone know exactly what the base material is?

The 3 pictures below are:
1) The shower corner
2) a closeup of the brownish spot you see in the previous picture to the left of the window
3) a closeup of the edge of it at the bottom corner of the window

We're trying to figure out what material to use to patch the holes and what kind of paint will stick once we strip the old paint.

Thanks!

[HiHoAgRV]

The endcaps are zolotone over fiberglass. I used orange paint stripper from the big box stores to peel off the paint. Bondo fills in the holes quite well.

[riowerks]

OHhhhhhh.... (bonk head with heel of palm....) I've seen references to the end cap, but I thought that was something on the exterior of a later model (maybe confusing it with bananna wrap?). Thanks for the clarification!