This is the Clark recoil and elevation unit. The Clark unit looks pretty well identical to Ian's. I managed to fit the Clark version into my Cromwell, so if it'll go that (it needed a shoehorn and lots of abuse

it should be an easy fit in other turrets. I had to design and make brackets for mine, as the gun supports in the Ludwig kit were totally unsuitable. You shouldn't have that problem with HL. I've posted a pic to give you some idea.

Apart from the eye-catching green colour of Ian's unit, it strongly resembles this Clark one here:

- Clark servo recoil in a Cromwell
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.