Installation Details Once the housing and stitch bolt centre lines have been marked, adjust the jig using the siting notches, and clamp it in place. If working round log stock, screw and shim a level section of 2 x 8 planking in place as a base for the jig. Note the brass guide and the 2" end-grain auger. Also shown is a smaller guide for the tension bolt hole to be drilled in the abutting member.