Its ok the mod on the Vectra C is slightly different the bottom inlet pipe has a tapered cover which is removeable with a flat screwdriver. Lets the air into the whole airbox instead of half of it, the filter was dirty on back half. The square box I discribed was the maf box and wasn't a problem as long as you don't disconnect so I'm informed. K&N panel filter ordered for Wed, Thurs will let you'se know how it performs. Thanks.