A couple more upsides of the Weigand mount are:That's exactly what I'm going to get for my GP100 6" stainless. I love it and can't wait to get the Weigand mount and get a scope on it for hunting.
They fit almost any Ruger with a adjustable rear sight.( I mounted the same one from my GP to a single six)
They leave no witness mark on the frame when you remove it & go back to the stock sight! A true win win