I didn't even mention items 5 through 10 (UPC Z28, sheet A4), which were added to the AIM on 6-2-69 (?). I believe these were a stop gap measure before the locking mounts were available. In fact, item #5 is called a "STOP"! It's a LEFT HAND item only, so it kind of adds to the above chart. Note the P/N 3886466 shows A.R. (As Required), and the P/N 3939728 shows only 1 being used.
For service requirements, I believe the 3886466 (non-locking mount) was attached to the right side of the engine and the 3939728 (locking mount) was attached to the left side of the engine!
For production, I have a feeling (no proof) that locking mounts were never used on the 302, but a stop gap measure was applied at some point during the production run. My copy of the AIM shows the date, but the month is kind of light and I can't be sure it's a 6 (June). Does anyone have a better copy that shows the month?