[old_tv_nut]

The bad one I had had gone to air and then wouldn't keep vacuum after Scotty's attempt to rebuild and seal it. I volunteered it for a dry run of the leak tester that was first demo'd at ETF some years back, and it turned out the leak was at a very small ding on the edge of the metal-metal face seal, not at a metal-glass seal.

That leads me to think that it is best not to risk damage removing and replacing the tube if it is securely mounted in the cabinet.

Also ditto regarding every CRT package I have seen ships it face down.