I'm afraid that I'm far from an expert.
However I did place a green tritium-vial in the groove of a Ti tailcap.
I used Loctite glass-bond gel (which cures under UV light).
I just flowed the glass-bond gel over the tritium making sure that the tritium
was completely submerged.
Then I placed it on a table in the sun and left it there all day.
At night I took it in the house and used one of my lights with a royal-blue
luxeon to help it cure.
Because I don't actually have a UV light, I had to be patient and wait
for a few days for it to set really hard.
Its now completely sealed and the epoxy is transparent (like glass),
so it shines through very well.
I'm sure the whole process would be far quicker with a UV light.