Thanks for the vote of confidence Dicky (not quite sure it's justified
). Anyway here's what I did on my model:
1. From the plan determine where the drive line is in relation to the aft frames. In my case the drive line intersected frames 3 and 4
2. Mark and drill the frames with a hole the same diameter as the prop tube. This is done before the frames are fixed to the keel.
3. As planking progressed offer up prop tube to hull, aligned by passing through the holes in the pre-drilled frames. I did this before planking was finished to give easier access to inside the hull.
4. Mark point of intersection of tube with planking.
5. Drill hole and expand with file as required, checking progress with prop tube. I also used a spirit level to ensure no that no bend was being introduced into the tube.
The attached pictures should hopefully make the process a bit clearer,
HTH
Doug