Hey Ordie - Bouldering under the Mcivor Highway bridge is a great training venue and definitely worth the ride of 12km! It is great for endurance - The holds may seem a bit slippery, sharp and hard at first but persist and it gets easier. Practice traversing along both walls and aim to be really precise and delicate with your feet placements. The more you go the better a climber you will become.
There is also some really sweet bouldering at Mt Alexander which if you get the chance you should check out.