i am not sure you can get a carbed 3s??? it has a 2s in it which is still a 2 litre but it is only a SOHC engine. i put a 4ac carbi on it. the mods i have made are as follows:
raised float level to suit the 2litre
seriously modified jets
converted to a double pumper
and removel of elec choke and summer/winter actuator
it goes pretty sweet now that it has the rolla carb on it. but the automatic really lets its potential down. so you like them do you? this is actually my brothers one but i have one similar that i am turbocharging the 22re. they are both on there bellys