Hopefully this link works once YouTube has finished thinking. Anyways. This was about middle of the way through many sets at 135. Had some interesting times trying to get my back as straight as possible with a stick along my spine (including at one point belting the thing to me so I didn't have to try and hold it in place.) I don't know that I was overly happy with any of the sets I did, but I at least figured out that neutral spine does not mean hyper extending one's lower back. (Ouch..)