I'm not 100% convinced on the ether part. Actually, I'm thinking ether in a different way. I don't remember any mention of a backfire. Some of the wording in the original post is odd to me, but I'm getting used to it. The OP said that he tried to start it with the block heater, "but it wasn't getting it". I assume that this means that it didn't start after the block heater being plugged in for a couple of hours. Then, with the ether, it "cranked up". To me, this means that something is turning over (like a starter cranking), but am learning that some people say this to mean that the engine started running. After that, I doubt that it would be an ether fire. The engine was running when he saw the fire and there wasn't (assuming) a backfire. If there had been a backfire, I could see where there may a small possiblity to light some of the oil from the CDR on fire. Either way, I would think that the air going into the intake should draw the fire away from the "fuel" and put it out. My guess would be that the glow plug wires were still disconnected at this point, but the system was working fine. Since the OP said that it was underneath the back of the intake and not inside it, I'm guessing that a glow plug wire was laying on something flammable. Diesel fuel? oil? penetrating oil? an over shoot of ether? When the ignition was turned on, here came the heat to start the fire. Now there was no mention of whether or not the ether was sprayed into the factory air intake at the front of the truck or directly into the intake manifold itself. Now "a couple of shots" of ether into the intake manifold should cause preignition of the ether in the engine if it all went into the intake manifold, but again, no mention of this either. So that makes me think that the first shot of ether could have missed the intake manifold which is easy to do, especially if you're in a hurry, like I'm guessing that he was. Of course I may be way off the mark on all of this and may be completely wrong. I just like to think outside the box sometimes if what's inside the box doesn't make complete sense to me.