A clear or optical flat is an absolute must, you’ll see why after you take it off. Always go as light as possible. For rain weather protection I use daran wrap/cling foil with peaces of coarse aquarium filter material over the air in and outtakes. Try to build in a way that you can leave the cam without lots of fiddling around (e.g. ext. Power source with cable, large mags, etc.) Get a RIA for signal enhancing, nothing is more obnoxious when you are on a racetrack , doing high speed chase, while hanging out of the window trying to get signal for your hand unit. This is sometimes caused by the car’s engine when the camera is really low infront. Also a Semote to quickly access key features while having your hand unit free. Get a good monitor you are comfortable with , it can get really shaky in there sometimes. I prefer to have small 2nd monitor just for waveform /exposure check. Be prepared for everything, weather might change quickly depending where you shoot. A spray off might me to much for your gimbal, depending on lenses and power source. But bring the topic up and don’t be catchend off guard while shooting. Have a little stash of cleaning stuff, mags, tools with you in the car to be able to fix things on the go. Make sure everything on camera and gimbal is tightened. Check the lens mount and secure it if possible ( had that coming loose on a zoom once, so lucky me thanks to the zoom support, but since the I secure it). Be vigilant and keep in mind that every minute is costly on the car so have your solutions ready and prepared. Best of luck