No no, epoxy does not normally bond to plastics. Find out what the housing is made of, polycarbonate or acrylic
. Then yes, you COULD use a special epoxy (West "G" series?) to bed
a 1/4x20 or other stainless nut to the bottom of the case. However, you'd get a better bond by taking a piece of the same plastic, 3/8 thick and maybe an inch square, and having a machine shop tap the threads into the center of it. Then fusion bond that to the case, using whichever solvent matches that plastic.
Or take that piece of plastic yourself, drill a hole in it (neatly, drill press) and press a "nutsert" with the right threads into it. Cheaper than the machine shop, if you can find nutserts locally.
Better cheaper faster neater.
Conventional epoxies on clear plastics? Nuh-uh, one day months down the line, you get a nasty surprise.