Smith's temp gauge question

[RestoCreations]

-My car is going to Mecum this week and unfortunately i am out of time. I have no idea why the gauge would suddenly fail, but im going to take a wild guess and say that i must have kinked the line when reinstalling the sending unit after moving it from one location on the intake to another.
-How in the world do they put ether gas into the tube and then seal it by soldering? Im really perplexed as to how they seal the tube enough to get the gas to remain and also how the gas doesnt combust when they are soldering the tube onto the fitting.
-If only there was a way to convert the gauge to read off of an electrical sending unit mounted in the block.

I might have to just swap everything out to autometer. I can get a full set here in a day and do a quick swap. I hate to do that, but it might be my only option. I cant sell the car with items that arent working.

[Blas]

The gas can be inserted in the end bulb frozen as a liquid and the line would be evecuated of air, then the final solder done at the gauge end of the tube. They can be repaired but replacement is the best option. I have one available from a new chassis that had shelby gauges installed at delivery. But we are a long way from each other. Perhaps just purchase a new unit and put it in the trunk.