I will leave the diagnosis to others who know drivetrains better than I but it does sound like a bad trans. However, I noticed the driveshaft/trans alignment in your picture is way on the right side of the tunnel. I can't show a good picture because of the convertible support panel but I believe my driveshaft passes over the center of that trans mount and cross support member so that the driveshaft runs right down the center of the tunnel.


The cover over that flywheel is a good idea too. I have bottomed in stuff enough times that I would not have wanted that chewing up that gear. I hit a chuck of ice back in the 70s and had to replace that cover. It might have done some serious damage if not covered.