1988 Ford F-150 Negative Battery Cable

First you are replacing the neg cable right? You mentioned where it is hooked to the starter that would be the positive cable. If you are replacing the neg cable anywhere on the engine block it good. Now if it is hooked to the starter then that is the possitve cable. What you will need to do is disconnect the cable from the battery and remove the starter and you will find that where it hooks to the starter there is a stud with a nut then the cable and a nut. Just hold the inside nut and remove the outer one. Hope this helps. Let me know if there is anything else.