The best way to tell if your concrete is cured enough, is to try to scratch it with a nail or screw... if you can barely put a scratch it with either of those it is good to go!

The worst thing you can do to a fabricated structure is to handle it too soon. Once you get everything in place and the concrete poured around it, it needs to remain undisturbed until the concrete has set. Moving/disturbing it before the concrete has set will loosen the structure from the concrete and all your work will be in vain... I know this because I make my living working with concrete.