It is the original number on the drivers side post. It is a 1954
I know a 100 is a half ton
150 a 3/4 ton
250 a one ton
280 is a ton and a quarter.
300 is a ton and a half.
350 is a 2-ton.
450 is a 3-ton.
It goes higher and I believe there are models like a 400 that fit in the middle...
If you still have the original motor its a 302 judging by the serial number.
