I you are borrowing the picker, I’d recommend building an overhead crane with some chain falls. I use mine ALL the time and I can do all my truck stuff by myself if needed. Cabs, engines, boxes, frames; it’s handy. I bring in eyes when fresh paint is involved though! It will make that box a breeze by yourself. 4 ratchet straps to the corners, 2 straps to a chain fall and up you go. But ensure it’s level as you lift (adjust if required), and you will be able to move that box with great precision, and yes, I rolled my truck under it and out from under it numerous times. I highly recommend this to you. My only regret? I should have built its base a little bit larger for stability purposes.
https://photos.app.goo.gl/hsSEBfZ2E6TRYcw78