battery ground

this 87 sable is still running hot. Examined starter relay wire and insulation is melted at last 3 to 4 inches from starter mount. This is my first ford product; so does the battery ground have to go to starter stud bolt? This sable's ground is attached to different part of engine. And would it cause motor to constantly overheat to where the starter lags and drains battery if it doesnt catch the first couple of cranks. Please help!