Safari gear question, a little different I think ....

I am heading to Tanzania to visit my daughter in late July and while the point isn't primarily safari, we do plan on doing a short (3-4 day outing) to Serengeti, Ngorongoro, and likely Tarangire and obviously want to capture it. My question is whether to take my current kit which is quite heavy or maybe really shake it up and buy another light weight mirrorless setup. Currently I have a 1DmkIV and would plan on taking a Sigma 120-300 and 1.4x, a Canon 17-40, and probably a Canon 100 f/2 (that probably won't get used on Safari but will for sure in Arusha and Zanzibar). The mirrorless would be so much easier to travel with and I do have experience shooting with them (pretty successful even with indoor sports). I also know that they have improved vastly in terms of tracking and ISO performance over even the past couple of years. An optical VF would be a must for me if I go that route.

For those with experience on safari, what would you do if your trip was as limited as mine is going to be and why?

The longer the lens the better imo. I rarely ever use a WA lens when I go on safari.

I would say your current kit is fine. The 1D4 is a great body but obviously not as good at higher ISOs as the newer kit. The 1.3x crop will come in handy too.

I was in Namibia last summer and had 2 lenses for my 7D, the 17-55 f2.8 and the 100-400 mkII. I primarily used the 100-400 for almost all the wildlife stuff and the 17-55 for the "other" shots