Not to sure on SI rego. I know the number plate says SI.XXXX! I think you have to fill out a log book of where and when you drive the car. You can only do so many kay's in the one year. Peter said that I should be good for SI rego as its not my primary car (the ute is) and its a perpose built race car. I will ask the rego people and see what they say. But I dont want to pay $460 a year for rego if I only drive in a handfull of rallys a year. You can understand that, hey?