Hi Matthew, Good question, I’m not sure as this is my first go at this and I have no local contact with any experienced Wayfarers. I’ve posted the picture in order to ‘fish’ for any helpful info. This is how I believe the centreboard bolts in. The bolt,68mm long including a 5mm deep hexagonal head has an 18mm brass washer then a 26mm copper washer (I suppose any noncorrodable matierial will do). This in turn sits on a rubber washer 26mm. This set up will compress onto the centreboard casing. The shaft of 7.86mm will pass through the board. I have filled in a 10mm hole with epoxy resin and drilled a neat hole of 8mm, making very sure this is square to the length of the board,ie at 90 degrees across. When the bolt emerges on the other side through the casing, the first washer on is the rubber followed by the 26mm then the 18mm then the whole assembly is tightened up so that the rubber washers compress to stop water ingress through the bolt holes, being below the waterline. Finally a locknut is put on to hold the whole thing at that pressure. There will be no washers or collars in between the inside of the casing and the centreboard allowing free movement controlled only by the friction brake assembly on the forward edge of the board. How does all this sound? Thanks to everyone for the help and advice that has got me so far. Let me know how you go on Matthew. ‘Cordon Bleu’ sounds as though you eat well on board! Cheers. Anthony and Julie