The owner kindly let me photograph this slightly different way to secure the outboard well blocks.
Apparently it was done because the self tappers securing the latches pulled out of the blocks, and there were only so many times you can replace the previous self tappers with larger ones. Having said that, this method of securing appears to give slightly faster and easier fastening.
The approx 30mm by 30mm L section glass fibre has been bonded to the top of the block (suggest you grind away surface gel coat to get a solid bond to glass fibre), and then flow coat has been painted on to give a similar finish to the body of the block.
NB: Flow coat is just ordinary gel coat with wax solution, plus the normal hardener. The wax solution stops the stickiness you get on the surface of ordinary gel coat.
A similar L section piece of glass fibre is bonded on either side of the outboard well, and the standard bolts then slide into drilled holes. One drilled hole is just visible in the upper left of the above pic, and the water in the well appears in the bottom of the pic.
Quite often the bolts lose the stubby little finger hold thingy. It unscrews. So probably worthwhile keeping a spare bolt catch assembly in your spares box. At least with a spare you can replace it quickly and get the block secured.