In the process of cleaning/replacing grounds, discovered this uncoupled lead. Anyone know where this should go? (88 n.a. GTU)

 

Right behind your hand on the firewall there should be a 1/4" male spade that it plugs into.

 

You can make a better, heavier gauge, ground cable to replace that for fairly low cost.

 

just as a side note. on the right side of that picture, there is an eyelet with two black wires leading to it. this gets bolted to the rear housing by the vacuum rack mount. if you don't do this the car more than likely won't run.