[morzh]

No, I have not.
A few times when I had to replace Candohms (the very first was a Zenith 9-S-262) I simply used the wattage that would be appropriate to not worry about the dissipation. My personal preference is 3x the dissipation. I mounted them on a barrier strip which then was bolted to the chassis.

You obviously could try to glue the resistors, but then you 1) have to make sure that wherever it is mounted, it will not fall under its own weight, should the cement soften. 2) Nothing is mounted on that chassis nearby so local heating (which could be pretty intense) while warping the sheet metal a little bit (some chassis are thick, some like Zenith's are thin) could not crack anything. A resistor in the air is still OK if sized correctly, but will not warm the actual metal as much.

This said, that red RTV they used as a gasket between the exhaust fan and the combustion chamber in my furnace probably would hold just fine.