Im not using the sierra stalks for switching lights dipped/main and want to use something like this mounted on the dash:

http://www.cbsonline.co.uk/product/Large_Rotary_Headlamp_Switch_ROSWHL

Ive had a read through the IVA manual and am not sure if this will comply?

In addition am I correct in understanding that as far as dials, if they protude less than 3.5mm they have to have a 'blunted' edge, if more than 3.5mm they have to have 2.5mm radius?

Those exact switches passed on my car however i had them sat into the dash with my design so not sure if that stopped the IVA man getting his cone around the switch.

Stick it in the exempt area:
http://www.locostbuilders.co.uk/gallery/Exem.jpg

then it only has to be blunted, which it seems to be.