my mate decodes almost the same as me
Vin number
1st digit: GM line number: Pontiac
2nd digit: T = Esprit
3rd and 4th digits: Body type number: 87 = Sport Coupe
5th digit: Engine code: U = 305 c.i.d, 2-bbl V8 (1978)
6th digit: Last digit of model year: 7 = 1977
7th digit: Assembly plant location: N = Norwood, Ohio
8th through 13th digits:
Production number starting with 500001 for 1972 models and 100001 for 1973-80 models