It's worth noting that with the school holidays, you should book in advance as they limit the number of visitors to the park.
We entered at Malelane Gate, the nearest entrance, drove up the H3 to Skukuza rest stop near the Paul Kruger Gate, where we had lunch and visited the souvenir shop, then exited the park on the H4 at Crocodile Bridge, approximately 150kms.
The gate closes at 6pm and the time differs throughout the year, you are fined if you are late back to the gate. The speed limit also varies and is monitored by radar.
We saw 4 of the Big 5, Elephant, Rhino, Buffalo, Lion but sadly no Leopard, as well as many other animals and birds and quite a few stupid drivers, blocking the road to follow the Lion, leaning out of an open window to take a photo of the Lion and 2 large 4x4's that blocked the road between a Mother and a baby elephant, as they filmed the elephant in distress, we got out of there as quick as we could, rather than wait for Daddy elephant to come.