Tommy Mason bought a custom Ruger #1 and I traded him out of the rifle. It does have a factory barrel with quarter rib for scope mounting. Does anyone have or make Island style bases to replace the quarter rib on the rifle now?

NECG, perhaps...?

Well, yes you can put a NECG/Recknagel rear base/island on it, BUT; Ruger factory ribs have four screws and two locating pins. If you remove the rib, you have a mess of extra holes that will never look good.

I have a Swarovski 3x10 on it now and it looks fine, I thought a 4x12 might be a little nicer. I have medium ruger rings on it now and it seems to be great fit.