These are various pictures of symmetric tuner construction and the finished product.
Note that in our tuner the rollers and caps are mounted as pairs of devices. This greatly simplifies mounting the components to the mid-plate, but also allows for more rigidity between the devices. This also allows us to color coordinate the mounting hardware with the outside case color. (yes this is trivial, and not required, but we're building a quality product here. The quality doesn't stop at the front cover).
Included in these photos are pictures of the roller inductor drive system (drive belt), air variable capacitor drive system with shaft RF isolators and vernier reduction drives. You can also see the capacitor dial skirts on the picture of the unit's front cover. The dial skirts are driven by the reduction drive, which provides for highly accurate tuning, especially when the point of resonance is extremely sharp.
Use of this tuner in the shack has proven that this design is both efficient and a solid performer. We can tune 1.0:1 on 160 - 10 meters on a dipole that is "short" for 160 meters. The addition of switched fixed capacitance allows for tuning highly inductive loads on bands like 160 meters. No additional fixed capacitance is required to tune any antenna that is 1/2 wavelength or better on any band.
See this section for information on Symmetric Tuner efficiency: Tuner Efficiency Proof