If you would like to have a third reef that does not require you to go up to the mast, try the solution i have on my B34.

Fix a small block with a fixed becket into the knot of the second reef.
take a third reef line from the cringle through this block then down to a block at the mast foot.through a deck organiser and back to an extra clutch at the cockpit.
When the second reef is set this brings the small block down to the boom so that the third reef, when required is set by pulling the third position down to the same small block.
It works a treat and as a bonus is a great way to drop the main, as a downhaul when i am on my own or in severe conditions.
Contact if you need more detail.