You take the dish with mount OFF the pole first. Then, use a shovel to dig out the pole with the cement. Once you get dug around it, you can use a long pole like a 4x4 to level it up and out. Or if you have access to a bucket-tractor, you can put a chain around the bottom of the pole and the tractors bucket, and then just pop the pole right out of the ground.
This all supposes that the ground is reasonably soft. If it's very hard, perhaps you can soak it well with a hose first to soften it up.
Now when you get it home and decide where to plant it, just dig a hole big enough to clear the cement circumference (and a bit more) and proper depth. Put a bag of gravel at the bottom of the leveled hole, and level the gravel. Place a cement patio paver at the center of the hole on top of the gravel (keeps the pole from sinking). Plant the pole on top of the paver, and brace it level North-South, East-West with stakes and some long boards. Then mix up some more 60 or 80lb bags of cement in your wheel-barrow, and shovel it evenly around the pole and domed a bit above ground level (to keep rain from sitting there and loosening the ground, dome shape helps it roll off and away) Don't forget to re-check that the pole is level both ways before the cement hardens! Lay the empty paper cement bags on top of the drying cement, and soak them with water every day. It helps keep the cement from drying out too quickly. Wait at least 3 days or more, and reinstall the dish with mount.