Backstay Tensioner SO37.1. Here are some shots of "Nesika's" split backstay tensioner.
The long shot above is at basically no added tension.
The shot of the adjuster tackle bottomed out above precedes the long shot of the position at max. tension.
This was necessary because, even with the turnbuckles at maximum shortening, as shown above, the forestay remained too slack.
The final installation involved shortening the overall length a bit.
Bill Prendergast - SO37.1 - Nesika