Specifications from the 1964 Registered Owners Manual

Dimensions (Inches)
Overall Length including Bumpers
      All Models Except Station Wagon   215.4
     Station Wagons 210.3
Overall Height (Loaded)
      Sedans and Hardtops 56.7
      Convertibles 55.7
      Station Wagons 57.8
Tread - All Models
      Front 61.0
      Rear 60.0
      All Models 120.0

Axle Gear Ratios
Your car will be equiped with an axle having one of the following gear ratios:
3.00:1, 3.25:1, 3.50:1, 3.89:1, or 4.11:1.

NOTE: The gear ratio may be identified by means of a tag on the rear axle housing or the code number on the warranty plate.

Refill Capacities (U.S. Measures)
Cooling System 19.5 quarts*
Engine Oil (Including Oil Filter) 6 quarts
Fuel Tank:
     All Models Except Station Wagons 20 gallons
     All Station Wagons 21 gallons
Rear Axle:
      All Models Except 427 C.I.D. engine
      and Locking Type.
5 pints
      Used with 427 C.I.D. engine and Locking Type   5½ pints
Standard Transmission 3½ pints
Multi-Drive Merc-O-Matic Transmission 11 quarts
Steering Gear 0.7 pounds
Power Steering System:
      With Air Conditioning 2 pints
      Without Air Conditioning 2.5 pints
*Add 1 quart with heater

Refill Capacities (Imperial Measures)
The Canadian Provinces employ an Imperial liquid measure which is 1/5 larger than similar units of liquid measure used under United States standard. If the approximate equivalent liquid capacities are desired, Multiply the specified U.S. measure by .83 to obtain Imperial gallons. Multiply the Imperial measure by 1.2 to obtain the approximate equivalent in U.S. gallons.

Point Gap (Inches) .014-.016
Dwell at Idle (Degrees)   26°-28½°

Spark Plugs (Autolite):
Type BF-42
Thread Size 18mm
Gap (inches) 0.032-0.036
Torque (Lbs.-Ft.)    15-20

Multi-Drive Merc-O-Matic Transmission:
      Speeds Three Speeds Forward, One Reverse
      Type Single stage torque converter with three speed
fully automatic planetary gear train
Manual Transmission:
      Three speeds forward, one reverse (Fully synchronized in all forward gears)
      Four speeds forward, one reverse (Fully synchronized in all forward gears)
      Overdrive with second and third gears synchronized

Radiator Filler Cap (PSI)   13-15

      All Models except Police and Taxi 8.00 x 14
      Police and Taxi 6.75 x 15
Pressure (PSI)*:
      All Models Except Station Wagons   24
      Station Wagons:
           Front 24
           Rear 28

* For considerable high-speed driving, or heavy loads, add 4 pounds to the recommended cold pressure.

This info taken from the 1964 Mercury Registered Owners Manual