Back in those days, cars were a lot easier to 'special order'. You wanted a red car with a green interior? They'd build it. You wanted a full-size Chevy with a straight six, 3-on-the-tree? They'd build it. Today, it has to be one of the regular 'package' bundles.
FWIW, my '89 Crown Vic LX was a special order car - complete with a 6-digit DSO code. Fully loaded LX, with just about every option AND the '5.8L Police' package. I have the factory build sheet. In the remarks section it says 5.8L Police.
Car was special-ordered by the fire chief of a small town in NJ as his 'official' car. One of the perqs of his job was he got to keep his department car when he retired, but it was required to have the police package. Thus he used department letterhead and special-ordered a loaded Crown Vic LX with a police pkg, just a short time before he retired... I bought it from his estate... and no, it isn't red!
Car has leather seats, power windows, power seats, power locks, cruise, tilt, cornering lights, 1/2 vinyl top, additional lower body bright trim, Premium Sound am/fm/cassette, power antenna, rear window defogger, vent windows, a/c, dual remote power mirrors, leather-wrapped steering wheel, lighted vanity mirrors, full deluxe wheelcovers.
Police package consisted of heavier frame, solid suspension bushings, heavy duty police springs, police shocks (1-3/4" piston - same as truck shocks!), beefiest sway bars, biggest brakes, 100amp alternator, power steering cooler, aux trans cooler, engine oil cooler, 140mph certified calibration speedometer, 'anti-static' ground straps everywhere, dual exhaust, traction loc rear end, heavy-duty 15x7 wheels (that's why no 15x6.5 alloy turbine wheels), radio-ready antenna hole in decklid, and the 5.8L (351W-VV) engine with police-calibrated trans.
Weird one-off cars? They're out there!!!