I did this job earlier this year, on my own, on my driveway. Not too hard but you do need to buy / rent the tool for pulling the old bushes out and pressing the new ones in. You also need oxyacetylene or a good blowtorch so that you can bend the exhaust hanger out of the way.

If you're fairly mechanically competent allow half a day the first time you do it. You can probably do it in half the time next time around.