Then I think you're misreading then. As ricer as super street is, I doubt they'd say something so wrong.
Black top sr's do have the fins cast into the head - and so do a very, very low number of redtops (which is why some think they were blacktops with swapped redtop valve covers before they were shipped over). Nobody really cares all that much.
54c pistons are just a different cast than redtop pistons. You can see the casting stamp on them. The undercrown design is different as are the oil squirters - all revised designs found in GTiR's and every blacktop.
I stole these images but added some markings so you can see: