Someone asked if I would show my davit tackle rigging tool if it worked. It does work fine, so here it is.
It is made from a hunk of sheet styrene 30 mil thick. The tongue where I make the tackle is about 3/16 inch wide, and the edges rounded. This represents the two strands of line around single blocks. On the Dreadnought the tail (twisted wire) goes into holes cast into the boats (one could drill that hole for boats without a hole). The opposite end of the oval goes over a little projection on the Dreadnought- it could be glued to the davit. One could put a glob of glue on each end to represent the block, but on a 1:350 scale the block would be hard to see anyway. The idea is just to get a double strand of some thin material.
I used thin varnished electrical wire. I haven't looked up the gauge yet, but it is about 7 mil. I salvaged it from a transformer when I junked an old TV.