[Lamar]

Hi PeeCee – I’m one of that guys that did the vinegar wash on a 60s Piano 36. I haven’t opened this one, but I have opened two other ones, and they had foam-like stuff between the compartment walls and the back cover.

I later found out that this stuff is similar to, or is, accordion sealing tape. Maybe that’s what you’re seeing? I ordered some from Amazon but haven’t actually used it yet.

I will now sneak back under my rock and let somebody knowledgeable about your exact model chime in. 🙂