416,

I'm in the process of scrapping the 1/4 rib altogether on my No.1 450 #2, and mount an NECG island sight over the front set of dowells. The rear dowells and screw hole, will need to be filled in, barrel re-polished & re-blued. It'll look a whole lot better than the rib, and I have zero plans to scope this beast anyways.
Just thought I'd throw an alternative your way.

Jeff