Thanks, Duck!
Forgot to finish the last post. The Midway order was a couple of trigger springs for my Ruger M77, a 3/8" dovetail slot blank, and another WGRS (Williams rear sight) and a 3/16" square notch WGOS blade to go with it. Here is a pic of the documentation that came with the blade. It does indeed fit the WGRS base. However, my eyes won't focus very well on the rear sight even at arms length so I'm not sure I'll keep it on any of my guns. I can report that on my 2300KT with 12.75" barrel, at arms length the Crosman front sight pin fills the rear notch about 1/2 way. That leaves 1/4 of the width of the notch as air-space on either side of the pin. That is how I was taught that open sights should look. Also, I haven't shot it yet but it seems that this 3/16" tall WGOS blade on the WGRS base is going to be close to the right height for the 1700-023 Muzzle Brake and 2300-028 Front Sight Post with plenty of adjustment. I will let y'all know for sure when I can shoot it.
Cheers,