From a cold start, the choke plate should be mostly closed. Over the first couple minutes of the engine running and warming up, it should gradually open all the way and stay open.
Regarding getting a carburetor with an electric choke, this is the one I bought
http://www.nationalcarburetors.com/l...partnum=nd4478
Since I have a 1969 truck, the throttle linkage needed to be the old style linkage. National Carburetors built this carburetor for me with the correct linkage for 1969. I'm sure there will be others who reply to tell you about their choke setup.