I just got through moving a couple of vacs I wasn't using down to the barn to get them out of the way and while I was out there, I decided to bring the 1205 I got from my parents' attic up to the house to do a side-by-side comparison with the one I've had and used for the past dozen years. As I said before, they're almost identical--both are from early in the Consolidated Foods era, likely 1969-1970, with the light teal door panels and no pigtail plug-in, but there are a couple of minor differences: the one from the attic does not have a tool clip and the arrows on the sliding blower covers are different. The arrow on the attic machine's cover is a raised red outline, while the one on the machine I've had for several years is a solid, raised red triangle, meaning the two covers are even from different molds. I have no idea which is the earlier style or if the two styles ran concurrently.
I think it's very likely that that the attic machine came with a tool clip from the factory and it was later removed as that machine has a much higher serial number (Y93663R) than my other one that does have the clip (Y12112M). Had the attic machine had a lower number, I would have assumed it came out earlier in the run, after the pigtail plug-in was deleted but before the tool clip was added to the 1205 line. I have no idea what the different letters at the end of the serial numbers signify, production facility perhaps?
The idea that the attic machine originally had a tool clip is further supported by my previous observation that the machine had been taken apart before yesterday's handle replacement, as evidenced by a stripped screw head on the cord winder assembly. There are also a few scratches on the aluminum top plate where that clip would have made contact with the metal plate, just behind the handle. The clip could easily have been lost during that earlier disassembly or perhaps even have fallen off sometime after the tail end of the handle pulled loose. The handle was intact when we found it except for the two little pins that kept it in place at the back. I have no idea when the tail end of the handle actually broke.
While I had the two machines together, I also decided to plug them in and do a rudimentary side-by-side suction test, placing my hand over the opening. The one from the attic is indeed slightly quieter and has just a little less suction. I tested both with the bags they had in place, which could account for at least some of the difference. Having both machines running at the same time while plugged into the same outlet seriously dimmed the overhead lights. I only kept them running like that for about 30 seconds for fear of overloading the circuit.
For your enjoyment, I've included some photos of the two machines. The one from the attic is on the left in each photo:
