Hi Richard,really nice rebuild you have going there. I think you'll have a great, tight rig when you're done.
For glassing around tight radius structures, like deck to hull, you might want to try cutting biaxial strips from your cloth, presuming you have cloth and not precut tape. If you roll out the cloth on a table, put a straight edge across at a 45 deg. angle, and cut strips on the bias at whatever width you want. You'll find the biax lays right around those corners, with no puckering. I do this with the leading edges of sailboat foils, like daggers and rudders, and it works great. If you make a wet out table, you can pre-wet the strips of glass and roll them right out on the boat. The other tip I have, is to use a carbide scraper, about 2" wide, to cut down the hard edge "bump" that you get from a selvedge tape edge, or any thick overlap of cloth. Faster than sanding, and no dust.
Steve's method for installing Beckson plates is exactly what I do as well, whether in a wood bulkhead, or in a fiberglass deck.
Going back a ways in your process, for filling old screw holes and such, I like to rip a 3/16" or so strip of soft wood, and make plugs by sharpening the ends a little, cutting to length (say 1"). Dip the plug in epoxy, and drive it into the hole, trimming flush after curing. That way, you don't have to worry about a big air pocket half way down the hole when using putty alone. Just my 2 cents worth on that point.
Get this one done, and build yourself a new boat, selling off the restored gem to finance the new one. I've been doing that for years to keep the chain of boats flowing.
Cheers!
Jim