I recenty purchased an O'day 23. I would like to step the mast with the boat on the trailer to check and tune the rigging. However, I need to level the boat to check the mast rake. The question is- How do I find level? Can I place a laser level (aren't toys wonderful) on the waterline paint or boot stripe? How about the cabin floor? The bottom of the keel? Somewhere on the deck? Any ideas will be appreciated.Thanks