The last few bits

 Orion OSB R+ program box/battery checker. One very cool bit of kit, Very easy to use and set everything up plus it also checks batteries.

 Now a transponder at last. I've wanted one of these for years and finally have one now!

Not super neat but it will do. I'd rather it be more forward, I was thinking under the shock tower/above the steering rack but wiring would be a pain so beside the servo Tom Cockerill style. 

Now all that's left to do is get a couple shorty packs, Hudy Set up station/tools, MuchMore charger and go out to race.