Howzit Paul,
I find one of the best spots on the bushmans is off the sandbar floating restaurant. They cool with letting you fish into the night there off the boat if you just lock up after yourself. Get hold of plenty of mud prawns and you will definitely catch some kob, mostly small ones but still fun, as well as one of the many grunter in that section of the river. Just drop your prawn into the lit area from the spot light, literally right off the edge of the boat.
You can also net mullet there right in front of the parking lot. Guys also fly fish off the boat for kob and grunter and have a good success rate. Otherwise you can drop shot around the base of the bridge (on both the kariega and bushmans). Odd grunter and plenty of yellow belly rock cod around there...
Anything else let me know...