Re: 1967 Sears / Gale Sovereign
HI xv. Weclome to iboats. Cool new toy you got there. For starters, your "Gale" motor is made by OMC, which also made Johnson/Evinrude. As a result, many if not all of the parts are interchangeable with OMC models of similar vintage. You may also hear your motor referred to as a "Big Twin", which is just a generic term for the arge 2 cylinder, 2 stroke motors OMC made at this time. They're well regarded, reliable, easy to work on and parts are still readily available, but they are gas hogs. Here are some great links that can walk you through a tune up from top to bottom. You can even get routine replacement parts right here at ibooats.
http://www.duckworksmagazine.com/06/columns/max/index6.htm
As far as the boat goes, there are only a couple rules when it comes to aluminum boats (a.k.a. "tinboats").
1.) Never use Pressure Treated wood on and aluminum boat as the preservatives within it will cause electrolytic pitting in your hull.
2.) Instead use high quality, exterior grade plywood such as Aruaco brand available at Lowes/HD and seal it using a variety of methods. The best ways are to seal it using either 2-part spreadable epoxy, or fiberglass mat & resin. Both methods work great, but can be a little pricey and messy. You often have to order the supplies too. However, you can also use several coats of Spar Urethane or high quality exterior grade paint. They won't seal the wood quite as well, but with care they should still last many seasons. (I like old school Rustoleum Oil Base Enamel)
3.) Use Stainless Steel hardware and/or aluminum pop-rivets throughout your boat. Dipping them in 3M 5200 marine caulk/sealant prior to installation, especially for through-hull fittings.
3.) As far as painting the boat goes. Sand loose paint with 220 grit paper, wide down with Acetone, let dry, prime with light coat of Zinc Chromate Self-Etching primer then paint.
That's really about it. Good luck. Holler if you get stuck.