I use new leads that are much thinner and coil one around the end of the old wire...I think it is more secure that way.
Glue I can't recommend any. I've tried super glue and it just comes loose. I've tried hi-temp silicone but not ran that tube enough to confirm hold....If a Base is still on a tube and the glue fails I just wrap the joint with electrical tape, and that seems to hold okay.
BTW the half of the connector that is normally part of a tube is called the 'Base' the half that is part of the chassis that the tube plugs into is called the 'Socket'. Correct nomenclature reduces confusion.
