During a power surge I lost 2 lighting fixtures. The ballasts
were glued in. I was able to remove them and got identical
replacements. My issue now is what glue to use that won't smoke
when they get hot.

 

Fluorescents I assume, Would be an excellent time to locate LED replacement bulbs and ditch those things!

 

I agree, convert to LED!

We can't see how your ballasts were glued in or to what. Best probably would be to use wire or zip ties to hang the ballast so it can get better airflow for cooling. As for what glue that depends a bit on what you are gluing. Is the ballast housing metal, hard plastic or plastic potting compound? What are you gluing to? Is it plastic, metal or wood?

I would avoid hot melt glues for obvious reasons though I doubt the ballast gets hot enough to melt the glue. You can use caulk type adhesives. I have often seen parts mounted with what looks like white silicone caulk/adhesive. Double sided tape can work depending on the application.

 

My fixtures are using Halogen Light Bulbs.

I would be glueing metal to metal.

 

Silicone glue would be fine for metal to metal.
You'd need to hold them in place until the silicone set.

 

Oh, it's a power supply or transformer. I would use a silicone adhesive and even regular solvent based silicone caulk would work.

 

I would just use some double-sided tape. No need to wait for the glue to set.

Example: https://www.homedepot.com/p/Gorilla-...5003/304544003