Can't figure out what year my 350 is! driving me nuts

[billybobjoe12323]

ok so i have a 1990 Chevy half ton with a 350 engine in it, when i bought it the guy just knew it was a "older" engine
i have been driving myself crazy finding all the numbers and castings on the thing because i finally got days off and I need to order parts for it but don't know what year to tell them anyway this is what I found:

casting number on drivers side: 3970010 with a GM 35 beside it
stamped number on passenger side behind alternator- 04201da and right below that was 46247

i tried researching for hours and it almost seems like im missing letters for the stamped ones and when i look up the casting it just tells me years 69-80 or something and i need a specific year. please help me!

 

[hurst01]

Why do you need a specific year? If it is 1969 to 1980, nothing has changed, anything will fit anything. All the bearings, oil pump and gaskets are all same. The only thing you will have to be concerned about is the diameter of the cylinder bore. On the drivers side between the transmission mounting surface and the base of the head there is a casting number like 5.0 or 5.7. 5.0 being a 305 and 5.7 being a 350. In approximately 1987 the SBC came out with full roller cam and lifters and center bolt valve covers.