Hi could anyone help me does this straight forward swap?
can the head be used on my 1200 engine A12? cheers

yes all from the a12 onwards heads fits on any block, if it's a round port i would recomend rather using the a15 head as it's almost similar to the gx head, ports are a bit smaller but the valves are much bigger than the a12 head and also the a15 (h89) head has the kidney shape combustion chambers which makes good compression

its all in here

read away.

the head from an early front dizzy a12 could be used, but not with out the reverse modifications that an a14/15 head needs to the oil passages to work. if its not a gx head, it may choke the engine even.

a14/15 have better flowing oval heads almost stock. look for one of them and save the hassle and costs.