Only times I've had VC gasket problems were on rounded head surfaces or valve train interference.
I pretty much always use cork, glued to the VC & a light smear of grease on the other face.
Obviously the surfaces must be straight & flat.
Make sure intake runners & pushrods & valvetrain aren't interfering.
On one engine, the rocker stands at the ends were actually holding the VC off the head. Beveled them.
On another, the VC spacers I used to make helped with the head surface and rocker clearance using OEM VCs.