Thank you! Yes, I have quite a bit of information to share on sextant use. I purchased a Davis Mark 15 on eBay, perfectly good for my purposes. There are lots of guides on how to configure a plastic sextant. I bought https://www.amazon.co.uk/Long-Term-Almanac-2000-2050-Reduction/dp/0914025104/ref=sr_1_fkmr0_1?s=books&ie=UTF8&qid=1520894883&sr=1-1-fkmr0&keywords=long+term+almanac mosly because I am tight :) All that is involved is a couple of additional calculations. To learn how to use it I found these video help a lot after that, practice makes perfect!