please click the button for the vid that will explain everything but i can tell you here so put the lever from the chest the block behind the piston facing the hole flick it it will say how dare you then wait then something will come out of the hole i used mod world edit but thats all for the big walls this took me a long time so pls give credit to me pls thanks <3 :) <3 you don't need the mod because normal minecraft does not read it