Ive "been there - done that":
Take the center insulator out of the tubing - then sand off all the
deteriorated fiberglass - then give it 2 coats of krylon clear spray -- good
as new -- every few years - do the same thing.
I have done this to my A3 and also to my R7
The A3 was purchased in 1982
The R7 was purchased in 1991
The center insulators look almost brand new.
Hope this helps
73 Bill N4JI
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