Erland , hi there .
You will need the 400 for use from the vehicle , the 180 with 1.4 converter will work from the vehicle also .
You are not going to get within macro distance from the car though , but most camps have a pool , or some have ponds , so keep the macro for here .
Skukuza has some ponds , and 2 swiming pools that will be good .
Satara has a bird area near the pool and shops , that has ponds , so that will be good .
Shingwedzi has some ponds near the shops .
I am sure lake panic , the boardwalk from the nursery (Near lake panic) , as well as the nursery itself will provide some oportunitys , I would budget on a good morning just at these 3 spots .
The day visitors area of skukuza has some small streams flowing through it , and is next to the sabie river , so this will be good also .
When you are done there , go over the low level bridge near the day visitors area .
The low level bridge out the back of shingwedzi camp will be good .
Most of the sand roads cross low level bridges , where the water flows over these bridges , and is normally around 10-20 cm deep here , with reeds on either side , as well as open water , so I have found these to be good to .
Sand roads I can think of of the top of my head with good spots are -
the road from gudzani dam to gudzani pan S41, along to sweni bird hide , and the bridge near there (Satara camp)
The road from letaba to olifants , along the river .
The talamati area can become quite flooded in places , with lots of pans next to the road .
Redrocks road , towards bateleur camp , there are 2 low level bridges crosing the shingwedzi river along this road .
S114 from berg en dal to skukuza has a couple of low crossings , including the biyamiti weir road .
Whatever you do , dont get out your car at any river crossing , there are crocodiles in all the rivers in kruger , you will make an easy lunch .
Not to mention hippos , leopards , snakes etc that are also hanging about the rivers
Try let us know what camps you are staying in , I would say shingwedzi , satara and skukuza/berg en dal are ideal for what you are after .