Holley/Demon Carb stumble
I use Superformance gaskets and nothing else. Virtually everything else is usable at best and most of it is junk. You'll never scrape a SF gasket.
You are now getting to the point where you could have bought two billet blocks and been done. I'd use BLP or Braswell or damBest long before I bought anything that said Holley on it. In fact, I'd use ProForm blocks before Holley.