(Possible) Bad News
The last Epic 3500 I found has stopped running, apparently due to my trying to replace the headlight bulb. I put in a new one, turned the machine on, and it almost immediately shut off (the suction motor, I mean...I didn't even get a chance to power up the power nozzle). As far as I know, I used the correct bulb, so no idea what caused this; it could be the plug, cord, switch, internal wire, or the whole thing might be blown. There were no sparks or smoke or anything nasty, and it didn't trip a breaker...it just shut off like it was switched off normally, and now nothing happens when its switched on.
As can be seen from the last post, the cord on the first machine wasn't in the best condition, nor was the switch, so if the problem lies there, at least I can put on a new handle and cord assembly. In fact, the cord on this new find has also been taped, and the headlight bulb is burned out, but you can bet your life I'm not fooling around with this new one in any way.
Putting the best spin on things with regards to the first Epic, I got it for $20, so if its necessary to replace things, it won't break the bank, and it could be a fun project. I've never taken apart an upright like I have the canisters.