that's what i've been wondering about, keeping the matte from dipping between the vents and causing all sorts of extra work...i had thought of wrapping it real tight with fleece all the way around, then cut/sand the excess on the underside off, as matte always seems to sink on me...marcus38 said:brush side to side so the matte wont sink down in between the ribs of the vents. then sand,sand,sand and do it again and again till its smooth, u know the drill!!