3970010 was cast between 69 and 79 and was actually in some 302 engines but most predominately 350 in both 2 and 4 bolt configurations in cars and trucks.

V0412CKH translates as follows:
V = Flint assembly plant
04 = April
12 = 12th day

CKH was found on the following:
CKH 1972 307 with a Powerglide in F A X/Apollo/Ventura
CKH 1973 350 m/t, 4 spd, (L48) in F A X/Chevelle/Monte
CKH 1974 350 m/t,3 & 4 spd, (L48) in F A X

Your complete VIN probably starts with 1C80 17R457174

1st digit – This is the manufacturers identity number, 1 is Chevrolet

2nd digit - This is the Model Series, “C” is El Camino. If it is a “D” it is a Custom El Camino

3rd and 4th and digits - body style, 80 is 2dr Sedan Pick-up

5th digit is engine size and it’s always a letter:
D = 250cid L-6 1-bbl (L22)
F = 307cid V8 2-bbl (L14)
H = 350cid V8 2-bbl (L65)
J = 350cid V8 4-bbl (L48)
U = 402cid V8 4-bbl (LS3)
W = 454cid V8 4-bbl (LS5)

6th digit the last digit of the model year (engine replaced with a 1977?)

R = Arlington, TX (7th digit - This is the Assembly Plant code)

457174 = (8-13th digit, Sequential Production Number)

Hope this sheds some light,
Glenn