I need to buy a new carb, as my quadrajet is all worn out. What is the stock size of my carb. I am not sure, but I think that it is 600 cfm? Does anyone know? Also, is my 4-speed manual an SM465? If not, what is it? Thanks! 1977 Blazer w/ 350 GM crate motor 44 front/ 12-bolt rear, gear driven NP205 31x10.50r15 BFG All-terrain- Larger on the way!