So far so good, Jon.  Welcome to the forum.

You have an uncut 1894 stock from what I can see.  Do you have a photo looking down on the rear of the receiver?

As for resizing, Open MSPaint, "save as" a new file name, go to resize and resize in equal per cents on the vertical and the horizontal.  Never work on your original photo.  My camera takes 4 meg sized photos.  I reduce them by fifty percent and save.  Then I check the file size.  If I need to tweak it I just do a couple of percent.