Thank you all for the kind and informative replies, sorry for the delay replying myself, didn't quite get the time to do so yesterday.
Hi, welcome to BCG.
Certainly, your photography will be more than adequately covered with the
above system. I use a similar destination setup (Z9, D6, gripped D850 and 70-200 f2.8E), although I find often need the
ZTC14 on the 800 PF. The 180-400 TC and 800 PF, and at least 2 cameras fits fine in my
fStop Tilopa - the new model is much improved.
I've considered the Vanguard Alta Sky 68 to fit everything but unfortunately it's been out of stock here for a while, and now that it became available again, it's too late for me to get it in time for my departure... oh well..That one would have been my first choice tbh...
Carrying the gear on the long haul flight won't be a problem, KLM allows 2 hand baggages and up to 17kg combined (flying clipper class).
Hi -- it all depends on what you are going to shoot -- me it is Big Cats first. Birds are way down the list. Other folk Birds are top etc..
-- and how are you going to travel from Nairobi to the parks/reserves -- me I fly SafariLink and I buy a freight seat - I put my cameras in the cabin - SafariLink will sell you a freight seat at check in if you have too much gear. I only use SafariLink. If you are travelling by vehicle well there should be no limits.
NO - take both the Z9+800 and the Z9 +180-400 plus FTZii. I would not bring the D6 myself. But yes also take the 24-120 -- if this is a Z-mount? I is nice to take shots of the camp and travel shots generally. I seek to NOT change lenses in the field on a game drive.
TBH, I'm more into birds than big cats, however, who dares to say "nay" to shotting anything remotely alike to what you have in your Flickr?? Not me!
My link from Wilson to Kicheche is via SafariLink, but I don't mind for such a short flight (and most likely hand delivering at the plane) to have my backpack in the luggage compartment if needed (unless I'm being hit with excess of weight and it pays off buying a freight seat as you suggested, of course).
My plan is bringing both Z9, each attached to its tele (Z800 and 180/400), unfortunately, the 24-120 is an F mount, and tbh, I'd rather bring a D6 not only because of the mount, but also as a spare body just in case... I never change lenses while on the field either, that's why I'm not a big fan of external TC's...
As for when you are out in the vehicle, it's harder to say, as I do self drives with gear on front passenger seat (3 rigged cameras to avoid lens changes) - summarized my tactics
here
However, it will be a good plan if possible to have the pack in front of you, in the footwell, holding the Z9+800 PF and D6. This is where a pack with top lid access is a big help so you can keep the bag vertical. Keep the 180-400 TC to hand across your legs (never let it sit free to be knocked off the seat!) A kikoi over gear helps to keep off dust between shooting.
I'm considering hiring for at least 2 outings a solo game drive (a bit costly but it may pay off)...
My first trip to Africa was to Namibia, but I had a car for myself with a guide, so wether it was driving around Etosha in a closed 4x4, where I had all the back seat for myself, or game drives on open vehicles, space was not a problem since it was only me (and my daughter), plenty of space.
Pangolin drives or boat tours were also spacious, plenty of room at the boat to have gear lying around, but this time in Kicheche I'll be perhaps sharing with up to 3 more people (4 pax max per car). I hope I won't be on their way with my gear...that's a bit of a concern to me, I don't like to be disturbed, nor I like to disturb others.
While on game drives (or in a boat) I don't carry the backpack with me, just the lenses+bodies, free, placed on the floor, and a waist/belt bag for extra batteries and memory cards.
My main concern is/was the focal needed in those drives: wether 800mm was overkill or not, should I bring the 600/4 FL instead of the Z800... should I just go with the 180/400 on its own... I guess I won't decide until the last second.
Thanks again Andy & Fenton for the time and advice. I'll keep reading the info you both shared in BCG!
All the best, Marcelo