The early Panteras didn't have a 17 digit VIN, just 11 digits. I don't know if there's an online copy, but the 1971/74 Pantera Chassis and Body Master Parts Catalog FP-8085 April, 1975" contains the information you're after. It can be purchased from Pantera International - the orange book 2/3 of the way down the website
I'm looking at my copy, and on page 6 it gives the following example:
THPNLS01859
T - DeTomaso
H - Assembled at Modena, Italy
PN - Pantera
L - 1971 (Calendar Year)
S - July
01859 - 1859th unit built
Page 9 covers the year codes...
L - 1971
M - 1972
N - 1973
P - 1974
The month codes for 1974 are:
C - September
D - November
E - December
H - June
J - May
K - October
L - January
M - July
P - August
S - March
T - April
Y - February
Hope this helps
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