In thinking back on the "Super Stock Years" for Chevy and Pontiac it had to be 1962, and ONLY 1962. Although the 409 was released in 1961, they were not really a showroom floor commodity at the time, they were in short supply. In 1962, the 409's were plentiful. By 1963, Chevy really did not have competitive NHRA legal S/S cars. A 409 equipped '63 Chevy was out classed in NHRA competition. Yes, they did have the 427-inch Z-11 package but it was not a S/S legal combination.
On the Pontiac side, 1961 was not really a banner year. Most of the Pontiacs in '61 were equipped with the Super Duty 389 engine. About a dozen 421 engines became available in 1961 toward the end of the year, and none of them were installed in showroom cars. By 1962, the 421 Pontiacs were showroom available. The lightweight (Swiss Cheese) Pontiacs were never classified as S/S legal by NHRA so for all practical purposes, Pontiac was also without legal competitive S/S cars in NHRA competition in 1963.
Ford did field a reasonably competitive S/S combination in 1961 (390-inches). In 1962, Ford bumped the displacement up to 406-inches, but the car was just too heavy. Too some extent, Ford was lucky that their cars were too heavy in '62, it gave them an incentive to release a light weight model in 1963, with the 427-inch engine. So, Ford, Chevy and Pontiac DID have light weight, big inch engine cars in 1963, BUT, neither Chevy or Pontiac produced enough of them to satisfy NHRA that they were "available" to anyone that wanted one. Only Ford did that, they kept building the light weight galaxies. I honestly believe that had Ford known that GM was going to kill off production of the the Swiss Cheese Pontiac and the Chevy Z-11 in 1963 after only a few were produced, I doubt that Ford would have stepped up (or maintained) production on the light weight Galaxie.
And then there were the Dodges and Plymouth S/S cars. In 1961, I can't remember more than 2 or 3 S/S Mopars in NHRA competition. In fact, other than the Ramchargers 1961 Dodge, who else was there in the Mopar camp? But by 1962, it was obvious that their new design was perfect for S/S competition. By 1963 they had bumped displacement from 413 to 426-inches, and in 1964, they released the Hemi. Ford took all the good parts they had installed into the '63 Galaxies and installed them into their Fairlanes in 1964. In essense, 1964 NHRA S/S became a Ford, Dodge and Plymouth show, and that pretty much ended the "Glory Years for S/S".
The only time that all the brands (Chevy, Ford, Pontiac, Dodge and Plymouth) were represented in NHRA legal S/S competition with full size cars was in 1962...