Thanks for the input. I'm looking at a more rust and abrasion resistant finish than bluing. I could hard-chrome it at Techplate like some of my other guns but I'd like a darker finish. Techplate usually asks that the parts to be refinished be completely disassembled, thus removing the cartridge guides.
I suppose I could always tap a hole into the cartridge guides, enlarge the holes in the receiver and put in an oversized screw from the outside. I wonder how the Winchester folks put in the original screws into the inside of the receiver?
best wishes- oldandslow