Rick is probably right. If David did not have time to practice with the SP12X front-end then where did he find the time to try the non-standard CRC front-end...?
Whatever he used, the base was a Corally chassis, so congrats to them. Als many congratulations to David, in my book one of the all time greats in this sport! Now on to the Touring Car Worlds Dave, although I hope Jilles takes that one