I'm looking at the book now and it all seems to make sense. Obviously some dims on page 170 are the longest length from point to point, where as on page 46 its measuring a different edge of the tube. I built mine as per the book, all clamped together to ensure the angles and sizes, before I tacked it.
If your still having problems, I can take some measurements off the CAD drawing, or off my build, if it would help you. Bear in mind, that it will only show how I did it, and maybe not the perfect way
