The McLaren switch panel looks sort of like a Cosworth MSP. The adjustment knob for brake bias is mounted to the left of the panel.
The suspension consists of fabricated “A” arms that support the GT3's wider track width. Ohlins 3 way adjustable dampers are used on all 4 corners.
The Ohlins are a thru shaft design. This means they do not need fluid room for shock shaft displacement and have no need for external reservoirs. They do have a small coaxial gas chamber for fluid pressurization though. This is pretty trick stuff.
The car has air jacks which are a big help on a flat bottom car with a lot of aero when it comes time to get it off the ground.
The 650S GT3 has a flat floor. The NACA duct like front diffusers probably feed the side skirts for additonal forward pressure recovery. The wood looking thing is a sheet of Jabroc which is a super expensive German piece of plywood which is really abrasion resistant and good for skidplates.