Could anyone advise on the following questions?

Date of manufacture? I was going to put todays date but should I put the date on the Sierra V5

Previously registered Again should I put the Sierra details in here?

Maximum design road speed 110mph? it says contact the manufacturer in the notes..

maximum engine power and engine speed out of the box the engine made 150hp at 6000rpm but now it has a big exhaust and zx9r carbs (untuned) so I have no idea. Also ideally I dont want the car revving over 5k rpm during the test as I'm not sure how lean its running at the top of the rev range!

design weights what?

immobiliser is this an electronic device only or can physical devices be counted?

Thanks!