[codefox1]

Look for screw holes if you don't have an actual shot of a stock set. A lot of sets did not have any back covers in that era, although I am willing to be stood corected by the experts.


In any case you can certainly get a sheet of masonite and roll you own. All it would take is measuring an cutting carefully with a saw, and large vents for the tubes. If there was not originally a back, best leave alone. If situated a couple of inches away from a wall there is little potential for hazards. And whatever I wouldn't want to be any closer than that.