Burris offers Pos-Align offset inserts for their Signature rings that allow a gun to be sighted in when the scope runs out of windage or elevation adjustment. The offset insert kit comes with 3 different size inserts and clear directions on how to move POI using the inserts. They are designed to change POI and securely hold a scope. I think they will work well on your 460, but I've only used them with 44 mag and 7-08 handguns.
Also, if you raise the reticle with a higher mount, POI will go lower.