I've had this happen before. Sometimes the middle spacer can bow the scales out a little to compensate where the wide part of the taper presses between the scales. Outside of that you could try to rotor out the inside of the scales where the tang hits (similar to the Puma scale design for the razors with the big grips on the tang).

Other than the middle spacer trick, and maybe a wider end spacer, I have not had much success with this issue. But then again, I was a little lucky with the degree of the tapper in the tang on those razors....

Good luck, and let us know if you come up with a trick!

C utz