Mark,
The rally conditions were a bit challenging for the smaller boats but compulsory water ballast on all three days meant that there were no capsizes, unlike last year. Quite a few breakages though.
The top and bottom high-load eyes of the jib topping lift both have an internal diameter of 12mm. The top one is sufficient to hang off the 8mm jib halyard, supported underneath by a 45mm external diameter parrel bead which rests on top of the top furler. The bottom eye is bigger than needed but was probably what I had in my bosun’s box at the time.
The line from the top eye to the top of the CL253 Clamcleat is 4mm Dyneema, spliced around the top eye and to the top of the Clamcleat. The line forming the adjustment mechanism through the Clamcleat appears to be 5mm polyester braid - Dyneema would be too slippery for this purpose. The bottom sling part of the arrangement is again 4mm Dyneema, spliced around the bottom eye and formed into a long soft shackle.
The black bullseye fairlead that I screwed under the jib boom may be unnecessary - I now just loop the sling line under the boom and rely on the rubber doorstop under the end of the boom to stop it from slipping off. That means that a long loop might do the job of the sling just as well as a long soft shackle, as there’s no need to undo it to thread it through a fairlead. I should say however that since I originally installed the topping lift, I've changed the jib boom from rectangular-section wood to a rounded carbon fibre spar, with less chance of abrasion.
Good luck!