Ok I don't want to sound like the safety police....but I will anyways.
I had my 2305 supported the same way you have in the picture. I reahed underneath to tighten the trany filter, the Fcunikg thing slipped off the jack and axel caught in the chest on the way down. To this day I don't really know how I got out. I think I kinda of rolled out from underneath. It happen quick.
My wife was around the corner in the yard and heard it fall and saw a tire roll out of the garage(must have leaning on the tractor or something). She though I was 33 years old having a heart attack, I was stuck on the floor with a ghostly white face unable to speak for quite sometime.
Sorry don't forget a secondary methode of support, even if your "not working underneath".........oops the socket rolled underneath.
Remember this: A wise man learns from his mistakes, but a wiser man learns from someone elses' mistake. Please learn from mine!