So… the Go2 socket was not as effective as I’d hoped. I don’t fault the tool here for several reasons. First, the bolt it was trying to grip is a flange style bolt (ed: it’s actually a hex bolt with a lock washer that’s slightly wider than the bolt head which has about the same effect). The small lip of the bolt made it difficult for the locking screw to find purchase. Secondly the space between the bolt and the body of the solenoid was just too small for the Go2 socket to turn. Under different circumstances this tool is probably a Godsend, but for me it was not what I needed.
That plan having failed, I proceed to waste another few hours trying as many tricks as I could think of to get that bolt to turn. I used a rotary tool to cut a slot in the top in an attempt to get a short screwdriver on it. That didn’t work. I put a torch on the bolt to see if heat could persuade it. All that did was set the insulation around the solenoid on fire. I even briefly contemplated welding a socket to the bolt. I’ve seen this done before, but I was reluctant to run current through the solenoid as it grounds to the transmission. I didn’t want to accidentally blow something up. Eventually I was forced to stop for the day. A combination of frustration and an aching back from crawling in and out from under the car had bested me.
But all hope is not lost. I have a set of bolt extractors to try, and a set of locking pliers with a long needle nose that maybe might be able to grip that bolt if the extractors fail. If neither of those things work I think I’ll have to execute a tactical retreat by putting a new (anti-seize covered) bolt back in the place I removed the old one from and move on to another task for the time being. Hopefully I’ll just get that damn bolt out and install the new solenoid like I had hoped to have had done weeks ago.