John Wilson or Ray Spence (found at Canberra Motor Works) are the only two worth chatting to.
The motor registry at Dickson can give you their contact details, or look up Rays business in the yellow pages (John may be in there as well)?
I have used John a couple of times, he was ok but I think his proces are up around the $1000 mark now to engineer something like you want to do (check with him and see), no idea what Ray charges.
The 3tgte will need to be fitted in a structurally sound manner (ie good engine mounts), you will need a catalytic converter, an unleaded fuel restrictor on the tank inlet, a brake upgrade (it won't need to be too fancy but some a little better and vented will keep them happy). PLus all the gereal roadworthy and safety type things, ie not too loud (it will be measured), not to low etc etc.
Give John a call and will tell you exactly what he will require.