99.9% sure wasn't enough I guess as they ARE different in the end, as you guys pointed out... There is some additional plastic on the black ones at the front of the arms next to the shock mount screw axles... prolly some kind of reinforcement scheme. They DO have the same part number though, that seems to be a running change.
I am slowly progressing on the build but I am desperately lacking time to update the thread with pics... every step takes WAY longer than I had planned. For instance, it took me about an hour yesterday to finally get the optional metal idler gear fit on its axle... they do mention in the instructions that the fit is "tight" but heck it was more than this as mounting it involved a vice, an brand new axle that was shot and went straight to the bin, a hammer, and the kitchen oven at 250degC...
Will post pics at some point, prolly after the race weekend
Paul