Is there any reason why headlamp covers (in my case - perspex), should not be fitted before IVA?.

Providing they meet the radius requirements and dont effect beam pattern I can see no reason.

If you fit them then it is much more difficult to adjust the height on the day.

Generally people leave them off until after the test.

My Fury passed with them on. As Matt says though it might be easier without. I had to remove one to adjust the aim (I'd set it without a full tank of fuel and was just too high when filled for IVA) and refit.

My J15 went through without, and even after passing an MOT the week before they "invited" me to adjust the aim on site at IVA.

Much easier to go without, and gives you something to do once you've passed IVA!!

OK...thanks...I think I'll play it safe and not fit......it was really an excuse to anything but the light wiring!.