Leaf springs are easy - you shouldn't have any trouble.
If you are changing the rear shocks, you should go ahead and disconnect them on the top end while the car is still sitting on the ground. If not, you can leave it connected and just swing the spring plate out of the way when you get it disconencted from the axle.
Jack the rear end up by the body and put stands under it, letting the rear suspension hang.
Remove the u-bolts from the spring plate to disconnect the axle from the spring.
Put your jack under the axle, nearest the side you are working on and lift the axle up off the spring to take the weight off. The leaf spring no longer has any tension on it.
From that point you can disconnect the spring from the body (front) and the shackle (rear), do what you need to (replace the bushings, change springs, whatever) and bolt it back together.
Rinse and repeat on the other side.
Good luck and have fun.