How To Align Extension Piece Holes (video.) wyndham January 27, 2021 23:47 Updated This video explains how to solve alignment and installation issues with extension pieces. Related articles How Straighten A Crooked Top Piece (video.) How do I install extension pieces? (video). Patio Pet Door Installation Video Can my pet door slide with my door? Installation behind your fixed glass panel (video). Comments 0 comments Please sign in to leave a comment.