On Sat, 17 Oct 2015 00:59:18 -0400, "Texas Kingsnake"
wrote:

I read all the excellent replies (thanks to all). Here's what I am going to
do. I will put on my long linesman rubber gloves, place a thick rubber mat
on the floor in front of the box and use a large insulated screwdriver to
see if the screw (it's slotted, not hex-keyed) will turn and by how much.


A wise electrician once told me to "never work on an electric with
both hands -- always keep one in your pocket." I still remember his
advice, but I don't futz around in a panel...