Thanks everyone for the initial support to Wead out the forgetfulness of not building for two years. The strong back is now finished and fully aligned. You can't trick a lazer beam! The alumin rail is by far the best way to go. It was my first go at that method and needless to say I will never go back. As long as all the cuts are made precise then it lines itself up.
Thank you nick for the useful video in your methods. It was my base point for the beginnings of this boat.

Dave g