@king_saturn: He fought SA Superman and they were complete equals. The Infinite Crisis fight is a big nerf to the character. Kal L > Superboy Prime.
Here, in Justice League of America #74, he stalemates SA Superman and they both collapse.
It's reinforced in the Bronze Age in Superman Family #187 when BA Superman admits Kal L is his equal in strength. This was around 1978, the time the first Superman movie came out.
And there are comics where he literally makes up superpowers or reverses time easily, etc.
Justice League of America 74 is borderline Silver Age / Bronze Age as the comic came out in 1969... Bronze Age Superman was official in the early 1970's... I guess it works though.