Hi,
I'm in the process of completely refurbishing\rebuilding my boats
masts. Looking for some thoughts on the following.

I'm replacing the wire halyard winches with 20std winches and spectra
halyards. The only winch model I could find that will fit the existing
pfd is a two speed. Are these commonly used for halyard winches?

Also the original sheave boxes on the mast were made up of two sheaves
with the wire running between them. These don't seem to exist anymore.
Can I assume that single sheave boxes will be o.k, exit angle not too
shallow to cause chafe?

I also need to replace the cheek blocks for my boom reefing. In the
larger block sizes that I require there are no models with curved bases
or adaptor plates to match the boom profile. Why is this, and any
suggestions on options. Reefing is external.

And lastly on the stripped back spars where some of the stainless
screw/bolt heads have sheared and left the shaft behind I'm intending
to extract or drill them out and epoxy the holes. Mast will be 2
packed. Do I need to do this, can I just grind them flush or would
corrosion still be a problem?

And lastly - fill no longer required rivet holes in the mast with epoxy
bog or put a rivet with zinc chromate in these holes?

Thanks in advance