Hope this helps:
D4DE-6015-BA;
D4 = 74
D = Falcon
E = Engine part
6015 = Block group part number
BA = Revision
The first two digits indicate the decade and the year;
A = 40's
B = 50's
C = 60's
D = 70's
E = 80's
F = 90's
G = 00's
The third digit designates the
vehicle model line;
A = Ford full size (Galaxie)
B = Bronco (70-75)
C = Torino/Elite
D = Falcon
E = Escort
F = Pinto, Maverick, Late model Falcon
G = Early Comet (61-68), Montego, Cyclone (69-76)
H = Medium &
heavy duty truck
J = Industrial
K = Edsel
L = Lincoln (58-60)
M = Mercury
O = Fairlane (62-68), Torino (69-76)
R = Capri
S = Thunderbird
T = F series or Bronco
U = Econoline
van
V = Lincoln
W = Cougar
Z = Mustang
The fourth digit designates the engineering group;
A = Chassis
B = Body
E = Engine