Ken,

I've not done a Stug, but I've done a Jagdtiger and SU 85.  Both times I fabbed a trunnion assembly and mounted servos to push and pull the trunnion.   JT had tons of room.  Su...not so much.  I know you've got more experience than I on these turretless wonders.  Pics are posted on the DAK website I'm guessing.  Not very advanced, but bulletproof in the field.
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