Mystery ground wire??

[JMAT]

Looking around in engine bay and noticed a small gauge ground wire attached to frame on PS near battery tray area. The wire has corroded and broken off from wherever it was attached to. Wondering if anyone might know what it could have gone to. It is a 87 ranger xlt with 2.3. Thanks in advance

 

[Haywire6000]

That is supposed to "T" off from the ground going to the block from the battery.