i have modded the standard head to accept the efi inlet , you simply mark out the non efi head with a gasket cut from the inlet manifold.
you do not need to open the head fully to the shape of the inlet manifold , you could probably be 1mm inside from the top the gasket without any problem

my uk import xr3i s2 has been running with this for a couple of months without a problem

efi head now to be fitted to my gotech t34 xr3