Bolt/screw 383119-S2 is a 1/4-20X1 1/2pan head, shown on AM0030 p25, 29 ,30 for 1969; AM0035 p23, 25, 26 28 for 1970. AMK carries it with the notation "similar". The original says "locking" in AMK Guide to Ford Fasteners, the replacement apparently has no locking feature.
Wing nuts for daily use, originals hardware for show.
Jim