I got them on Nov 27th as promised but didn't have a chance to test fit until today. Tesla's web site says to use the red spacer with "M" length screw. When I did that, the red pads of the chains did not pull up against the sidewalls of the tire as shown in the pictures on Tesla's web site and in every picture I've seen of these chains online. Some red pads (top two in the picture below) were an inch or more from the tire sidewall which causes the chain to ride close to the outer edge of the tire:
Using the red spacer ensures the red ball at the end of the silver arm coming from the lug-nut holder never gets closer than about 1cm from any part of the wheel hub. The instructions say to choose a spacer where the red ball never gets more than 2cm away from the wheel hub spokes (what they call "the rims"). However, the instructions also show all the red pads of the chain touching the tire sidewall and they show a hub that sits significantly deeper than the sidewall. On Tesla tires, ridges of the hub come out as far as the sidewall, maybe even slightly farther. So getting within 2cm of the Tesla ridges is like getting within 4-6cm of the style of rim pictured in the manual. Therefore, I switched to using the blue spacer and that worked much better to pull the chains on almost completely:
With the blue spacer, the red ball can hit the spokes of the wheel hub if you rotate it to point towards the tire sidewall. However, the instructions say to put the lug-nut gripper on the farthest right lug nut with the ball pointing down at the ground. Tighten the red gear-shaped handle as tight as possible, then rotate red ball and handle till red ball points over the center of the tire. If those instructions are followed, the red ball will not touch a hub spoke, though it comes very close in some wheel orientations.
Another oddity is the instructions on Tesla's site say to leave "max 3" links of chain between the center and where the chain locks in to some red plastic. The instructions that came with my chains say to leave between 2 and 4 links of chain, which means you can't pull the center down as close as you could if you went to 1 or 0 links of chain remaining. The instructions are not clear as to where you should count your 2-4 links of chain from, but based on the picture it looks like they want you to count from the underside of the red plastic to the end of the chain. There is always one link that's halfway visible coming out of the red plastic and I don't know if they mean that half link to be counted or not. I decided to count it so I was leaving 1.5 links of chain visible in both my tests. Actually, I seem to have accidentally pulled it till only half a chain link was visible when I installed the chain on the other side:
It's also possible that in actual ice and snow things would be slick enough that the chains would pull on completely with the red spacer. I did my tests on dry asphalt. Has anyone run in snow with the red spacer? Did you leave 1.5 links of chain visible between the red plastic and the center bar? Note that I'm not counting the final anchor loop as a chain link.
Anyway, I'm pretty happy with the chains overall. I won't know for sure how well they work till I have to drive in snow with them, but that could be awhile.