Where do I service the eng coolant on a 1994 crown vic? Is it in the reservoir or on the actual radiator?

I can only forewarn you about several things to watch for in hope of providing you with something to prevent you from breaking something.
You must also consider loosening the transmission mounts to free up the entire drivetrain. There may be some clearance problems at the rear of the motor and the Radiator hoses may not stretch, nor may the fixed A/C lines to the front A/C cooler allow much travel space.
The oil pan is not a lifting point, nor is the crankshaft pulley. The exhaust system is not flexible either.
Your best bet is to look at the actual motor mount and see whether the mount is flush or has protruding studs. Flush shaped will be easier to handle. An 1/4 inch of clearance would allow you to slide parts through the opening.
You could still get another Expert to answer. I owned a 1994 Crown Vic and was underneath it many times, but never changed a motor mount on it.

What angle is the car parked when it does leak? The biggest problem that I have encountered with the Crown Vic is that the intake manifold is plastic and they have a tendency to crack, usually at the rear of the engine but sometimes near the upper radiator hose.

ECM LOCATED EITHER LEFT FRONT FENDER NEAR THE RADIATOR SUPPORT OR LOOK IN RIGHT FRONT FENDER NEAR EVAP CANISTER.

no a different style motor

it's funny to be reading about a similar situation i'm having. i also have a '97 crown vic, bought at a municipal auction.
of course, running the a/c should put more load on the engine and produce more heat. but not enough to be concerned about. if you car seems to be overheating, the thermostat could be to blame.
while diagnosing a different matter, i noticed the coolant temperature at one point reached 217 F. i'm going to replace the thermostat as it may only be opening partialy. my temp gage is normally just above the half way point between the high and low marks. it hasn't gone any further towards the high temp mark to be alarming.
where is the needle pointing on your gage? have you replaced the thermostat?

Yes it is. They will need to be drilled out. Thats the best way, some people try to put bolts on, but I dont advise it.

YOUR ENGINE IS GETTING TOO HOT.THERMOSTAT BAD OR RADIATOR CORE CLOGGED AND FRONT GRILLE AIR FLOW BLOCK FROM DEBRIS OR THE COOLING FAN RELAY STUCK CLOSED POSITION MEANING BAD RELAY.

there is a alternator fuse on the relay center under the hood that is a large fuse rated i think at like 140 amps check it it probably blew

please rate, thx Coolant Recovery System NOTE: When the water thermostat (8575) is closed, there is no flow through the radiator coolant recovery reservoir (8A080).

Trapped air in the cooling system must be removed. A pressurized radiator coolant recovery reservoir system is used which continuously separates the air from the cooling system.

• When the water thermostat is open, coolant flows through the small hose from the top of the radiator outlet tank to the radiator coolant recovery reservoir.
• The radiator coolant recovery reservoir separates any trapped air from the coolant and replenishes the system through its radiator coolant recovery hose to the water thermostat housing.
• The radiator coolant recovery reservoir serves as the location for:
  • service fill
  • coolant expansion during warm-up
  • system pressurization from the pressure relief cap and
  • air separation during operation
• The radiator coolant recovery reservoir is designed to have approximately 0.5-1 liter (0.53-1.06 quarts) of air when cold to allow for coolant expansion.

push down and turncounterclockwise when it cool down.