Just as a follow up, it was Rogerbird that first suggested the insulator to me years ago when I was having a problem with another 2510 I had.
Don't know if you guys remember Yaesu Tom.
He also went down this road with these radios and removing the 38MHz pull off caps.
Caused all kinds of weird stuff, TX problems, high swr problems, feedback with the cover on that went away with the cover off and so on.
These things are really getting old, 1980's........
Now it is LCD displays that are "bleeding" , old parts and mileage that is causing them to get discarded.
I have the one Chipswitched 2510 left and a newer Lincoln.
All the rest got " retired"
They just don't last forever.
73
Jeff