Indeed Ford and Payen gaskets seem to be the bees knees. Christian was running 32psi on a standard gasket.
Your always guna have some carbon deposits thats inevitable! What colour are the plugs?
Being perfectly honest mate, you will do EXTREMELY well to throw the metering head at a wall/in the bin/at someone u dont like etc etc and fit EFI.
Altrhough i appreciate its a Series 1

so you may not want to but in terms of practicality and reliability........EFI is the winner hands down