Have a read throught this link
http://www.rta.nsw.gov.au...ctors/vsccs/index.html
 
then call someone on this list
http://www.rta.nsw.gov.au.../vsccs_bulletin_01.pdf
 
or this bloke
http://www.terrytoomey.com.au/
 
and ask them what you can and can't do legally with your car. Doesn't matter what anyone says one here or anywhere else cause it's the bloke who signs the car off as roadworthy that determines what you can and can't do.
Also ask how much they charge while you're at it and start saving up.

top fuel motor will fit. can be legally driven at you nearest drag strip.