Hey glad you like it! Yeah I admit the core panel is tough to get a feel for. If the needle matches activate you flip the switch to the right and if it matches deactivate you flip the switch to the left. It can definitely be hard to tell which is right though because sometimes the different needle positions are a little too close together. When its solved all the needles will be pointing at a third reading that's not on the paper so you can just brute force it that way as well.