Do any of you know anywhere that sells just the 4 center head studs to go from a single port to dp heads.

Also thought about just making some spacers if this wouldn't cause a problem later since some of these studs have been really hard to get out.

8mm or 10mm? You can't use spacers because the studs will hit the intakes,unless you are building a long stroke/long rod motor then you could use the longer studs.