
- topping lift swivel block - closeup.jpg (215.47 KiB) Viewed 20520 times

- Topping lift at top of mast.jpg (138.05 KiB) Viewed 20520 times

- Topping lift at boom.jpg (181.77 KiB) Viewed 20520 times
My setup has the topping lift line attached to the aft end of the boom with a carabiner, running over a cheek block at the top of the mast, and down to a swiveling block/cam cleat on the mast. I used it last week for the first time and I'm really happy with it. Most of my topping lift adjustments happened while I was also doing other stuff at the mast, so having the cleat there is convenient.
You can pull it tight and also pull the mainsheet tight when the boat's rigged but not sailing - that way the mainsheet and topping lift will pull against each other and hold the boom in one place. When you sail, you loosen it a bit so it doesn't interfere with the mainsail shape.
(My boat is a DSII, but that doesn't matter for a topping lift.)