They don't wrap!
on the Oday 23, the shrouds run along the end piece of the spreader, and are held in place by a rubber boot. The boot is shaped like a "T", with the long end fitting over the end of the spreader, and the crosspiece of the boot fitting around the shroud. The boot is held around the shroud and onto the spreader with tape. You can buy rigging tape (very expensive), or just use electrician's tape. I have used electrician's tape (a lovely shade of black) for six years on my Oday 23 and have never had a problem. Replacement boots are outrageously expensive. If your shrouds have been wrapped around the spreader, it means they are probably ruined and must be replaced. In any case, if they were the right length when wrapped, unwrapped they will be too long. Call Rudy at D&R Marine (his website is listed in the Links section of this site) for a good deal on new standing rigging. Rudy put a new set together for me a few years ago and I was very pleased with the quality and service.