As an alternative to modifying the Tamiya elevation unit, I just replaced it with a servo.

So far I've fit them in the Tiger (easy), Pershing, and Panzer IV (both kinda tight).

The fist Tiger turret show the original Tamiya unit, the 2nd pict is with the servo. When the turret is tight, the small the servo the better. For the Panzer IV and the Pershing I fabricated a mounting plate similar in shape to the old elev unit. The existing hardware was use to attach the plate, and silicon adhesive to hold the servo to it.