When you mock it up ignore the bolt pattern alignment on the head for now. Use the gaskets that fit the ports, again ignore the bolt pattern alignment. Set the intake on the motor with the gaskets. Be sure the intake is centered. if the port in the head is too high compared to the intake port, then stack another gasket on each side and recheck. If the port lines up now you can glue the gaskets together or have someone make the appropriate thickness gasket. I think cometic will do this. If the gasket bolt holes align with the intake ( they should) then this is where your heads will need to be redrilled to fit the intake bolt pattern. The original holes will need to be plugged as outlined in a earlier post. If the misalignment appears to be slight you may consider slotting the intake and gasket holes to fit the existing bolt pattern in the heads.
Check water port alignment and be sure distributor shaft engagement is correct. Also you will probably not be able to use cork or rubber end seals.
I would only consider this approach if you already have alot of time and or money in the heads or you really need/want to use these heads. Good luck.