I wasn’t going to add to this thread because Ordy put out the end-of-discussion-sign; after all, what else is there to discuss? The way this thread has unfolded, OP isn’t going to know which way is up.
First, the 9790140 is one of the best intakes ever manufactured. To this day, no one has manufactured a better one, maybe ‘as good as’ but not better. It’s 100% unbiased, documented fact, the reason you hear strong feedback. One of the no-brainers is its design. See how much additional cooling area your intake has than other intakes? Cooler air = denser air; denser air = bigger bang.
Second, stock Pontiac intakes are spread bore intakes. Spread bore means big bores in the back and smaller ones in the front, meaning a spread bore carb is a direct bolt on. There isn’t an upgrade for your intake, so it’s moot to discuss square-bore anything.
A Felpro #1233 gasket allows you to bolt any year heads to any year intake. Although it’s not included in gasket kits, it doesn’t cost any more than buying intake gaskets by themselves, and it’s amazing that the pirates don’t cash in on this one!