does any body know wat 5spd gbox fits on A12 120y engine with out to much modding cos the 4spd on its way out

This is what it says in the wiki.

What types of 5-speeds are available?

56 series trans
small, light as in original B110 4-speed with visible ribs along case. The 5-speed versions were 1:1 fifth-gear "direct [trans]mission" (non-overdrive)
60 series trans
smooth-case medium-size trans as in B310. These come in 60L (dogleg) and 60A (non-dogleg) varieties
63 series trans
large trans commonly used with L-series engines, a version was also fitted to A-series engines in B210s. The 5-speed version is a "dogleg" shifter. It was fitted to 5-speed hatchbacks from 1976-1/2 through 1978 model years, and starting in 1977 for Canada

Finding one will be the hardest thing, as they are getting a bit thin on the ground.

Next option would be to do a Toyota box conversion, contact Dellow in Sydney they should be able to set you up with all the bits you wil need.

Yes, all the transmissions can be used in a B210/120Y. In australia the Dellow option seems to be good unless you find a Nissan 5-speed for a reasonable price.

Details: wiki - 5-Speeds.

does a datsun 310 or 200b box bolt up

The box out of a B310 will fit, but a 200B wont.

what modds have to be done to attach. will it bolt straight on does a 120y tailshaft fitt in to the back of box and trans tunnel moddin

I dont think you will need to do any mods.

thanks for all you help and info

were the datsun b310 boxes over drive or not if not wat 5spd over drive will bolt on an a12 engine and were can i get one in toowoomba

youll have a hard time gettin one in toowoomba buddy, you may have to broaden your scope to the whole of australia.
and if you do come across a 5 speed to suit an a series, i hope you have a biiig wad of cash to pay for it.
these gearboxes normally go for between 700-1500 bucks depending on condition.
IF you can find one..