For future projects, memorize how it goes together before you take it apart... (If it's together when you get it). Anyhow....
Three lines running up the boom are probably the outhaul
and two reefing lines.
connects the the clew (?) of the sail, the corner on the bottom to the rear. It'll generally run around a block on the end of the boom and them up the boom to the mast. Where it goes from there is should be the hard part, and every boat is going to be different.... This is used to hold the clew to the boom and control the sail shape, i.e. more shape in light wind
flatter in more wind
On the back edge of the sail you will hopefully find some grommet'd holes for reefing points. They should match will holes in the front of the sail. The reefing lines should go up through these and back down to the boom (generally). The object is to pull the sail down, and make this the new effective clew. I would assume you have two reef points, with the lines starting attatched to the boom (possibly just tied to it) through the reef point on the back edge of the sail, through a block on the end of the boom and up the boom to the mast.
And, when it gets to the mast, the puzzle thickens. My suggestion would be to look at a boat that has a single
line block reefing, where the reef line then goes around a block in the front of the boom, up to the reef point in the front of sail, and back down to a block in the mast (or the deck
directly under the mast?) and back to a clutch
on it's way around a winch
into the cockpit
. (it wouldn't need it's own winch
, but it's probably better if it uses a different winch than the main halyard
, cause when reefing you will pull the reef line to bring the mainsail
down while slacking on the halyard
to allow it to go down.) But, chances are on a 27ish foot boat, this wasn't how it was setup before, the lines probably have a lock or cleat on the front of the boom, or on the mast near it.
Having done this some thing recently (I bought a trailer-able 30' boat that the mast comes down on, and the boom comes off before the mast comes down, and all the rigging gets taken down), I would suggest going over the sail controls that need to be there one at a time, and figure out how they should work, given the pieces you have, rather than looking at the pieces are trying to figure out where they might have come from.
The topping lift
will come from the top of the mast down to the end of the boom. This holds the boom up when the sail is down. If the sail is raised, this should be loose, to make sure you aren't hosing your mainsail
holding the boom up with the topping lift
The main sheet should run from the traveler (if there is one) to the bottom of the boom, maybe 3/4 of the way back or so. On a 30 foot or less, the sheet probably runs through a pair of blocks on each end (i.e. 2 pulley block on the traveler and 2 pulley block on the boom) and general a cam cleat on the end with the traveler for control from the cockpit