100 amp alternator...most likey a rear sway bar...and at least a 318 or 360 4 barrel...maybe even a 400..
Bigger alternator is correct. M-bodies never got the big block factory and except for the first few years the biggest engine you could get was the 318-4bbl. The hallowed 360 pursuit cars of the '80's were much rumored, never proven. I've seen cop cars with 318-2bbls and even a slant once.
The typical equipment was
an oil cooler, mounted to the hood latch brace with a return line going to a special hollow bolt on the fuel pump to spray oil directly on the timing chain. Chain was a double roller, no quiet gear nylon teeth set up.
Sure-Grip rear.
11" inch rear brakes. (even on the slant car I've seen)
Brass bushing in the block for the distributor
rear sway bar like Eric mentioned.
15X7 "cop" wheels
oil pressure gauge mounted in the dash with a special defroster switch located next to it.
The 318-4bbl had 360 top ends. Maybe that's where the rumors of the 360 came cars from, the uninitiated seeing the 360 intake and thinking it was an entire 360 underneath.
727 transmissions
Most usually have cast iron biscuits instead of rubber iso's on the k-frame, though I have seen others with the rubber mounts.
And I know I'm forgetting more.
Don't let anyone fool you about "cop" torsion bars. The t-bars are the same size as other F/M/J's, the cops got bigger balloon seals.
Look for the AHB code to determine if it's true, though usually the telltales will stand out: the hole in the a-pillar where it used to wear a spot light, the plain jane taxi cab interior with power windows.
And, yes, if you beat the bushes hard enough, they're still out there. I've got my eye on one right now, for a reasonable price.
