Daryl
Thanks for the suggestion, but I'm not a reloader. I decided to remove the muzzle block, and enlarge the opening for the right barrel which allowed me to shim it. I played around with difference shims until I got the barrels shooting bore width apart. I soldered both barrels to the muzzle block and all is well. At 50 yards my left and right groups are 1 1/2 inches, elevation is almost identical. At 100 yards my groups opened up to 2 3/4 with the right barrel almost 1 inch higher. For whitetail deer it should work fine.

respectfully
wcf