Drilled & reamed left controls with drill press. I had left CS-121 long @42" and discover the plans 37" is already way long. finished part ended up at 32"!!!
Made a jig from 1/4" ply to hold the stick vertical, (42mm wide, with a credit card spacer to make it fit). Made another jig to hold CS-124 bolt heads 1/4" clear of firewall when vertical, leaving 3/16" clearance at 20 right Aileron, and CS-124 vertical.