Here are all the backfalls. Each one is different length:

The pivot point for the backfalls will be a felt rail, not an axel like the coupler backfalls. I added a small piece of wood to the center of each backfall to give it more stability:

The roller board:

The sticklers rest on the tail end of each key. They push up the back end of the backfalls when a key is played:

The backfalls in their fan arrangement:

The front of each backfall connects to a wire that pulls down the front of the pallet. I used threaded collars from OSI to make the key-to-pallet adjustment easy.

The pull-down wires pass through lead discs. These discs allow the pull-down wires to move while keeping the pallet box almost airtight:

Here's a view from the back:

The pivot point for the backfalls is a floating rail. This keeps the whole system in constant tension even as the weather changes. The rail is an aluminum extrusion weighted with lead strips:

Here's a view of everything: