Here is the result of my Redhawk scope mounting project.
Ted Ulmer machined the top rib of my Redhawk to accept Ruger style rings. ($90) Ted does custom guns and likes to use the Ruger rings on quarter ribs etc. (Thanks again to Darrel H for the measurements.) I bought a Weigand Weaver style base instead of the Ruger rings so that I can mount my glass with Weaver quad rings that I already have. Everything mounts up great. It looks and feels very nice. The Weigand rail mount comes back over the frame allowing the scope to be mounted about 1.5" back farther than the Ruger rings. Thanks to everyone for your thoughts and ideas. Here is Ted's contact information.

Ulmer's gunsmithing
Spring Mills, PA
814-364-9230
ulmgun@comcast.net