[SA]EG4 b18c conversion

Hi, I juz purchased a eg4 converted with b18c engine from NSW to ADL. but the engine is not registered with the car. I am wondering anyone knows whats the process to get the engine registered with the car in ADL? Do I need to get a engerineer certificate? and Do I have to show the receipt of engine to the inspector? Some ppl said I do need to provide the receipt of purchased for the engine but I dun have it and the previous ower do not have either(engine conversion done by previous owner, not the one I bought from). Anyone here done a conversion in SA and able to teach me what do i need to do to get the car registered?thanks