My 120y coupe was an auto to begin with.. its not hard but i wouldnt do it again, just hold out and wait for a manual(i got sick of waiting and looking). Not sure bout the 1200's but i had to make up a custom gearbox crossmember as the auto tunnels are totaly different i think. its the little things that make it not worth while ie:gear stick boot/seal,fire wall clutch cable mount ow and the rego problems(ive yet to come to that i swaped the day after i got it registed) the only benifit to be had is trans tunnel size if u ever wanted to upgrade.hope that helps.