ok, so i've got a 3 series 12 bolt carrier in a truck, i'm going from 3.08 to 4.11, but i told the guy tha ti have a 3 series carrier, when he sold me the gears . Ok, i'm looing at the gears, and the 4.11 ring is approxx .110 thicker than the 3.08 ring. Is that about how tick a ring spacer is? or do i STILL need a spacer?, the gears are Motive, the part # is simply GM12-411?