Recently I picked up a 91 justy. Ef12 carburated, fwd 5 spd 3 door hatch. Does anyone know if the justys transmission will directly bolt up to a suzuki swifts G13B engine? I found a 91 g13B engine for a good price. I'm just struggling to find out how to actually swap this engine into my justy.

Welcome to the USMB.

 

I'm going to move your post to the old gen forum.  It should get some more replies there.

You might want to try a Suzuki forum as they might be more inclined to know what it it can be mated to. Might take awhile to get a response on some forums as they aren't overly common, maybe a bigger following across the pond, hard to say.

I believe it wasn't until later that the Justy became just a re-badged Suzuki in foreign markets. So the 3cyl in it and the attached transmission in yours are probably subaru only.

 

With yours being a FWD only one, there's no reason to keep the subaru transmission. Just use the whole suzuki powertrain package and splice the axles together.