Elemental HERO Captain Gold

This is because I've been running an E-HERO deck on and off for years, but I've been meaning to find this out, and since I can't locate it anywhere else, I will ask here.

The effect of Elemental HERO Captain Gold reads:

"You can discard this card to graveyard; add 1 "Skyscraper" from your deck to your hand. If "Skyscraper" is not face-up on the field, destroy this card."

Does this mean only the original Skyscraper or does Skyscraper 2: HERO City count for its effect as well? When me and my friends played we all concluded that it does and that you can use Captain Gold to add either Skyscraper or Skyscraper 2: HERO City to your hand. Is that move legit, I just to be sure. Also does that mean if Skyscraper 2 is face-up on the field does Captain Gold still get destroyed. (The reason behind this question is because that both of the other cards mentioned here have "Skyscraper" in their names)

You can only add the original "Skyscraper" field spell. This is very similar to the Dark Magician support, which I'll use as an example. Dark Magician support, such as "Dark Eradicator Warlock" or "Dark Magic Attack" specifies the usage of Dark Magician. You can tell since it says "control a face up 'Dark Magician'" or "by tributing a face up 'Dark Magician.'" If it were to be any Dark Magician, like Skilled Dark Magician, it would say "'Dark Magician' card."

Going back to Captain Gold, it can only search out and needs the original "Skyscraper" field spell to survive on the field.

I knew about Dark Magician support, I used to use a deck built around those. That's why I was wondering about Captain Gold, I didn't know whether or not the same principles applied here. So thank you.