Well, I agree with Bartamos. It's so easy to say "replace the Rochester B with something else". Well does the new carb fit w/o an adapter? Do you need to change the throttle linkage? Change fuel and vacuum lines? Change air cleaner? Change choke cable or change to automatic choke? Kick down if you have an automatic?
Seems like a opening a can of worms.
Finally, is the new carb you bought a lemon?
Seems easier to rebuild the old carb.
OP: take advice in the above posts above. I would start with checking timing and vacuum.
