308 into an LJ

Hi has anyone in NSW recently put a 308 into an LJ Torana? Checked the RTA webste in NSW its not to clear to me if this is legal.

Reason I ask I have just found a great project that I am considering to buy. Any advice on the conversion appreciated.

Car is currently unregistered & would need a blue slip, I cant begin to imagine what the RTA inspector would say bringing an LJ with a 308 in it for a blue slip

thanks