My World aluminum block required a head gasket that had different coolant holes on the bottom row. I got the correct part no. From Rich Nedbal AKA Mopar Rich. I had to order them from Cometic.
Mark
Sounds like the KB gaskets also. The KB block has the outer row of steam holes relocated away from the bore requiring a special head gasket and relocating the holes in the heads.
I had a head gasket sealing problem with the only KB street hemi block I assembled for a customer due to the sleeve height being to high at first and then those dang cooling water holes being so close the sleeves in the block
I ended up having to take the block and heads to SCE gasket company in Lancaster, CA to have them make me some copper head gaskets that would work properly
All the other head gaskets I had bought and tried where for the race KB blocks, not the street block
