Harken Blocks Upgrade or not?

Have a different main sheet system, mine has block for traveler, then only one block for boom. All pulleys (3) total are three rope wide. anyone familiar with this set-up? Do you attach (aft) to rear of boom? Looks like an upgrade, hopefulley it is.

Yep, sounds like it is an upgraded system with a single triple block on top (connected to the boom). It's a cleaner system than the original three single boom blocks with less opportunities for the blocks twisting.

The boom bale that you chose effects the forward force on the boom which effects how much mast rotation is induced. Most people go with the center boom bale. You may want to drill out the top two rivets on the bale, angle it forward a few degrees, and re-drill and rivet the bale. This puts the boom bale more inline with the angle of the mainsheet blocks.

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