To v3 and oril:
The Mac S and D are good boats. The swing keel (S) is nice if you like to be daring in the shallows. It let's you know by gentle thumps to get out of there. The dagger board (D) is said to be a bit faster (any good skipper can make either faster). If you enter any club races your handicap will be high so learn to sail or just have fun (that's us).
v3: Just go by the book and you'll be fine rigging her. One note I would add is to guess the age and bag of your main. Unless its' new, stand the mast up a bit straighter. Sloping it aft will cause more weather helm as your speed/heal angle increases. Stand it straight up and hold the tiller with your finger tips. DO NOT tile the mast forward of straight up. You can cause reverse weather helm and spin stern on rather than into the wind if you round up.
oril: Another alternative to muritic acid is Phosphonic acid. I know, you never heard of it. It is also used in swimming pools but they call it names like "Metal Magic" or "Stain Magic", etc. Unlike muratic acid (50% hydrochloric), it is mild and continues to work. It is good for removing stains, dressing up tarnished metal, and perfect for disolving calcium. Brush it on. Let it sit a few minutes and swipe the deposit with a putty knife. If it does not crumble off, brush it again and wait a bit longer until you find the right timing. You can dilute it if you wish. I use the above method and have a beer in between swipes. Calcium usually gone before the six-pack. It has not hurt our bottom paint at all. I do not know about other paints. Test a spot befoe you go all in.
BTW, works great soaking oxidized SS fittings and (off the boat) hard water stains, etc. around the house. We also use it diluted in one of those battery operated shower cleaners you see advertised. We mix it with water and reuse the bottle after the cleaner is gone. Wife loves it. No more shower scum. Always snow white grout lines.
About hull wax, our experience is that any good wax (car or boat) works as good as another on a trailer boat. We even use the spray on occasionally if we are too busy with back-to-back trips to buff it out. The real key is to protect the gelcoat/paint from oxidizing and from fuel and other spills in the water around marinas.
Good sailing to all