Chassis is equipped with a pan/tilt mechanism, controlled by two free channels. I used a small servos HXT 500.
Although I removed the excess copper plates, and I did relief holes, the weight was approximately 200 grams without a camera. TwinStar would carry this extra weight, but as the bottleneck proved too weak HXT 500 servo, on which is attached the lens with the other servo. Servo was shaking during operation and the picture was unusable.
I decided for the reconstruction. As the material I chose a lightweight poplar plywood. The design is similar but instead of horizontal servo I used a larger and stronger GWS Park servo. Now the movement of the camera lens is smooth and picture is stable. Moreover, I saved about 100 grams of weight.
To attach the chassis to the model I used strong neodymium magnets from old destroyed engine. I put two side by side, perhaps it will be strong enough. I gouge small shallow holes in the chassis and in the model also and glued the magnets by CA.
On camera, I added two microswitches, one serves for switching on the camera, the other as a trigger for recording. I removed a small plug, which had joined the panel control buttons. Then I tried to find the right pins which are activating the recording and solder a microswitch on them.
The last enhancement on Twinstar are the new engines GT Emax 2215/12. You can read more about them here