When applying Coverite Micafilm, you only really need to apply the Balsarite to the perimeter. If you want to adhere the Micafilm to the ribs, then get the Micafilm stuck to the perimeter first. Work out as many wrinkles as possible BEFORE you start any shrinking. Lift and re-stick as many times as necessary to get the covering as smooth as possible before you start the shrink the material and stick it to the ribs. This way, you'll be able to get a flawless finish.