Parts Bulletin PI-04-12/81 (issued 12/17/81) states "A fully automatic rear mounted radio antenna is now being installed on all DeLoreans"... It does not give a VIN breakpoint. But it does state that this antenna is also available as a kit (P/N 111291) for any owner who wants to convert from either the embedded or right-front-fender mounted version.
My car has all three versions. VIN 1141 came with (and still has) the embedded antenna in the windshield. A replacement right front fender (crash by a previous owner) has the hole for the mast antenna (with a temporary plug until I begin restoration of the body). And to overcome poor reception, I had the power antenna installed in the left rear.
Hank Breer
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