Don't know about a BX, but the work light connector that was on my L3800 harness was under the left fender, up around the rear light. In the photo the green connector is part of the work light kit I bought from Kubota. The work light connector on the tractor's harness was taped up, so it wasn't easy to see, and could be missed if one just looks quickly. On an older L model I checked out at my dealer, the work light connector was under the seat. You can try checking these locations on your tractor. Hope this helps.