All Ford components have a casting/part number , something along the lines of “C5AE-6015-A” which can be used to Identify the date of casting & it’s original application.
The first figure , “C” in our example above , indicates the decade of manufacture :-
B = 1950 – 59
C = 1960 – 69
D = 1970 – 79
E = 1980 – 89
F = 1990 – 99
The second figure, “5” in our example, indicates the year within that decade. “C5” being 1965.
The third figure, “A” in our example , indicates the car line :–
A = Ford
D = Falcon
G = Comet, Montego, Cyclone
J = Marine & industrial
M = Mercury
O = Fairlane & Torino
S = Thunderbird
T = Ford truck
V = Lincoln
W = Cougar
Z = Mustang
The fourth position, “E” in this case, indicates the engineering group :-
A = Chassis
B = Body
E = Engine
If the Item is a service part then the fourth figure indicates the division :-
Z = Ford division
Y = Lincoln – Mercury
X = original Ford muscle parts program
M = Ford motorsport SVO or Ford – Mexico.
The 4 figure number between the dashes is the basic part number , in this case 6015 is an engine block.
The final figure is the revision number , “A” is the original design , “B” would be the first amendment to the original design etc.
Thanks to Paul Garton for this info.