From this I concluded a few things:
1) This is an older model DFP since it still has the old style light-blue potentiometers with the little black plastic ball clips to hold them in place.
2) Kevin or the new owner has a pet (probably cat, dog or rabbit) with medium length light grey or white fur!!
(Or has an elderly relative with short grey hair that moults a lot!)
3) Kevin or the new owner enjoys eating potato chips while racing!
Have now reseated all connectors, removed the fluff and chips and taped the potentiometers and wires in place. Result? Done almost 130 laps of testing tonight on 2 circuits using 10 cars for another Pick'n'Mix selection and the brake pedal has not stuck or showed any signs of flickering at all!
So, in return for lending us his wheel, it's new owner gets it back good-as-new!