I have adressed problems like this before by machining the bottom half of the front ring a little lower with an indexible fly cutter set at a .500 radius (for 1" rings). This will make the gun shoot higher, and you can take care of the windage issues with the screws on the rear ring.

To determine how much to machine, try to get the scopes crosshairs back to about the middle of their adjustment and then determine how low it shoots at 100 yards. Let's say this is 20". Then measure the distance between the rings. Let's say this is 5.4" Set up a ratio: 20" in 3600" (100 yards) = x over 5.4". In this instance, x is .030. After cutting 30 thousands out of the bottom of the front ring, you must also cut .030 off of the "pad" where the two ring halves meet. Then lap the rings get full contact on the bottom halves.

You can also set the base up to shave a little angle from front to rear, but is usually easier, from a machinist standpoint, to just lower the ring. Shims will work, but they are generally regarded a "K-Mart"solution.