Toyota: 86 Celica ground wire?

First, *I* didn't take the care apart, and *I* didn't put it back together.
But, I do want to get it running and out of my driveway. I have an 86
Celica that snapped a cam shaft some time ago. Swapped the cam shaft, need
to do a little head-check (I didn't put it together, so I need to take it
apart and re-torque things). However, we're just trying to see if things
will crank. They won't, and I think it's because of this medium gauge
ground wire. It's yellow/green with circle lugs on either end. There is a
connector in the middle, indicating that it definitely goes to a removable
unit on one end.

Can anyone tell me where this wire goes? Head to something?

Thanks,

chg