I have been to South-Africa 7 times hunting, 2 of them with a .454 Casull revolver. On the other trips i have used my Steyr Scout in .308 with Swift Scirocco 165gr bullets. It is all about bullet placement, you go for broadside front leg and 1/3 up from the brisket or then you go for the engine room from a rearward angle, one option is the neck shot.
My Kudu was 284 meters from sticks, black wildebeest about 150 meters from prone, blue wildebeest about 100 meters using a fence post as a shooting stick and from an angle from behind where i used the "elbow" as an aiming point.
Other animals from 10 meters to 575 meters.
Baboons and especially vervet monkeys are great target practice !
Train to shoot with the sticks, either bipod or tri-pod, you will definitely mostly shoot with sticks because of the tallish grass.
Travelling with a separate gun case and ammunition case is a wise way to travel.
Choosing South African Airways is a good choice because they are used to transport safari hunters equipment and at least from europe to SA and back, they dont charge for the gun and ammunition any extra.
In SA at the Johannesburg airport firearms licensing office you have to have patience, be nice to the officers and you dont have to tip them anything (they might try but it is actually forbidden to pay them corruption money).
In the terminal you carry your own stuff, i dont trust the luggage carrier guys, seen too many discussions about the "agreed" price to pay for the porters.
At the firearms check in office you can tip the guys about 20 rands for each case, that will make them happy and they can buy their lunch for that money. Dont show them any dollars, handle only rands.
Be mentally prepared for TIA, meaning this is africa. The airport officials some times are quite reluctant to serve white men, especially if you are tall, well build, bald and your accent is close to afrikaner or boer english accent. Americans they try to rip off of their money.
Enjoy your hunting trip to magnificent South Africa !