All I would do to your BK1 is put the VLA arms and hubs on the front and rear of the car and you will be good to go. I ran that particular setup for a while and still somewhat prefer that over the CR... IMO my BK1.5 (.5 b/c of the VLA) turns much better in all aspects compared to my CR. If you need a setup for the BK1 shoot me an email and I will give you the setup I used to win the Losi Champs. Good luck.
JConcepts/Werks Racing Engines/Ironman Bearings/PowerMaster Fuel/VP Racing