I also believe the cluster gears are the same. I only had one Super II chassis and I thought it was a dud for drag racing since it was tied down with all those weights and the rear gearing was slightly different all of which slowed the chassis down. I sold the one I had a few years ago for 270 and I think they are going for even more now. Why, I don't know, I never thought much of them. They did come with braid from the factory which was a good thing.
the attraction is/was ..... they were engineered to race on professional commercial tracks against TYCO. Tony Perchelli (SP) was hired to help design the chassis because his custom AFX had beaten the TYCOs repeatedly in big competitions. Tony was still a teenager when he began working for Aurora and had to accept some compromise to his customizations in order to be able to mass produce the super II. they were designed for road courses and trying to maintain high motor RPM. the double wound 4 lam 4 OHM armature had a higher RPM capability than the best original AFX armatures. so the crown gear was changed to 19 teeth to take advantage of the higher motor RPM. SUPER II were a limited run production and came with set screw attached aluminum rear wheels. the case was very nice and I think I recall buying one via a magazine ad mail order for about $12.00 plus minimal shipping. the deal with that pre-order was that an additional 4 lam arm would be included. being the sneak I was at that time, I wrote Aurora when I got mine that the extra armature was not included and they sent me another one.
again, the Super II was designed to run on commercial tracks with better power supplies than the AFX wall wart. thusly they didn't live up to expectation on home layouts and were badly dissed in media. I took advantage of the money back guarantee and returned mine for a full refund. the deal was you could keep the "bonus" armature if you returned the car. I don't know what happened to those armatures, my brothers inherited my stuff when I got old enough to drive. they trashed most of it, but I remember that those arms in a t-jet paired with Super II dimpled yellow/blue oriented magnets was very quick.
so, while they hold no value as race cars, they are highly valued by collectors.
Sounds like you let one get away there Al. The one I had still had the original box which collectors like but I could care less about but I was glad I saved it for some reason or other. I had pulled all the weights off but it still had the original gears and armature, it was still a dog even without the weights. I had put a Camaro body on it. I had saved the weights however and was able to put it all back together including the original body which had broken in front where it mounted. I was still able to get 275.00 for it back about 5 years ago. If I still had it I would guarantee my 3G Outlaw car would beat it easily. Still I guess it went around a road track OK but that was and is not my cup of Tea, never was even with full size cars.