You have to put it in prior to putting the two halves together. You'll end up with a lot of it stuffed in the left side of the wing but it doesn't show and you only need enough of the lead coming out of the hole to wrap around the cabane a few times before plugging it in. Once you have enough sticking out you can cover the hole with a piece of monokote so all you see is the wire lead coming out. I think I covered this in detail in my full user review of this plane.