Update. I took bushveld's advice and found some HVAC aluminum tape and fitted a piece to the hook. It mic'ed .003". One piece of it completely put the gun back on face, with absolutely no light visible between the right barrel breech and the standing breech. I was really surprised, as this showed that the wear was really at the hook/pin joint. The gun, with the .003" shim on the hook, is as tight as a brand new gun. That tape is some really tough stuff it seems. My plans now, since I have been informed that tiging the hook is out, is to shoot it for awhile with the shim in place to see just how long it lasts and whether or not it "wears in" and loosens up again.
I've messed with cutting shim stock and getting it to adhere it to the pin on guns before, but this tape stuff is so much easier, if the thickness is right. When fitted properly it is all but invisible, no kidding, and the adhesive on one side of it makes it a natural. I intend to see how long it lasts before going any further with repairs.
Thanks everyone for the valuable information. Especially bushveld and Dennis. You may have saved me considerable grief, not to mention funds.
SRH
