If I recall correctly, the distributor is held on with one bolt - the one that allows you to turn it to adjust the timing. I remove that one bolt and just pull it out as I recall. You'll want to make sure you look at the rotor and note where it's pointing so it can be re-installed in the correct position for ignition timing but other than that, it comes right out.
This is the bolt which needs to be removed
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This picture shows the distributor in a 1951 six cylinder. I believe the four cylinder has this bolt on the bottom side of the distibutor as opposed to the top but it looks the same.