frame ID #s

[mightymouse]

hello this question has probably been ask a lot. sorry.but i have a 72 gmc numbers on title matches Vin tag on cab . its got a Chevy front clip that someone changed along before i got it .frame and bed has been shorten. I'm wondering what frame i have . the numbers that i have found on frame are 7s157067. is it a 67? if anybody knows id really appreciate it . i guess it doesn't really matter I've powder coated it and have a lot invested in it .so I'm gonna keep it . just would like to know..thanks m.mouse