D3?
So in the end I opted for a used Canon 400mm f/5.6, it seems like these have strong residuals and are the 'entry' level options for both sport and wildlife primes. The intention is to sell it after the trip and I'm very pleased with the copy I've found, its had a filter in place and looks barely used (less so than the new copy I played with in Harrisons), carry case etc. (watch this space if anyone is in the market).
I've also been reading a lot. I found this quite
good. It looks like AI Servo, down-tuned if possible (don't think the 5 series bodies offer this).
Central point which then expands to surrounding points after first lock.
AV priority and keeping the shutter faster than 1/500 until I learn to pan (I can just about do a first bus).
Front lit. Sharp eye preferably with a nice catchlight.
Metering - I'm still not sure on this one, matrix with EV should be ok on a blue sky but looking down into the gorge I can't tell if its going to be spot, or center weighted or plain manual.
Other fieldcraft links or information on AF settings are very much welcome. Its going to be impressive how badly I fail at this.
Of course a flash and a fresnel are going in the bag too, I can't help myself.