all the pointers are there --- ALSO get the smallest lightest camera you can scrounge or borrow. A lot easier that expensive/compex vibration mounts !! Heavey needs fluid dampeners or multi-ratre rubbers, light gets away with a bit of foam.
If you've some cash around and intend using the in-car footage to attract more sponsors then invest in a bullet cam with an AV output to a cheap camcorder. ( and no vibration mount required )
"A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'