Tim,
- For the main sail tack to mast 1/4" anything should be plenty. I am thinking of using a piece of 1.75mm lash-it with enough for 3 wraps should be plenty. This only needs to counter the outhaul forces as the cunningham will deal with the vertical.
- My outhaul is 3mm spectra with a poly cover added for chafe protection. I have a 6:1 total purchase on the outhaul. 2:1 primary at the clew (just run through the grommet, no block needed) and a 3:1 internal to a clam cleat on the bottom at the forward end of the boom. Seemed to be plenty of power to adjust when needed under load.
- My Cunningham is 4:1. 2:1 primary goes from a block up through one of the holes on the gooseneck, up to the grommet in the sail and then back down through the other hole where it's tied off. Then a split tail secondary doubles the purchase. Jon, I'd recon a cunny would help you depower more when you are single handed. That something I spaced on one heavy day, we fought the boat during the sail, and then I was derigging and it was loose as it could be.
- My main and jib halyards are none stripped 1/4" vectran which doesn't like the sun so much. I would definitely shrink them a size, go with spectra and strip them next time. Just make sure you have gloves for the main if you dial in lots of prebend and are 1:1. Main halyard is 2:1 too with enough tail to reverse the whole line down the road so I'll probably never have to replace it at the rate I'm going.
- Spin halyard is a heat preset polypropylene line. It's plenty strong and has a little give for taking up the shock of a huge puff. It's nubby stuff and again requires gloves or hands of steel. I'd probably do something different next time.
- Spin tack line is stripped 1/4" spectra cored line (NE endura braid I think).It's green for "go".

no problems with it yet, but I haven't flown a spin in much wind yet.
Mast is 305" long, jib exit is about 240" as I recall of the top of my head without looking at drawings or the rules. I don't have the exact exit heights but they are staggered between 12" and 20" as I recall. Conservative rigger would only strip to about the mast base as a max or even a little higher to provide a little chafe protection at the mast exit and turning block. You'd have to guestimate your block and cleat location. Note, I moved my turning blocks down to the cabin top instead of being on the mast base to improve the angle to the cleat. It was a bit too much angle and there was some slippage there.
Good luck. Rigging is exciting!!!
Kevin.