Serial numbers on 55 Kaisers used the Willys method of numbering. If your car is a 2 dr it'll start with 51467 and if a 4dr it'll start with 51367. The next set of numbers is the actual car serial number.
The 2dr serial number range was 5001-5044.
The 4 dr range is a bit trickier...they run from 5001 to 5226, however, there are a few serial numbers in the 11000 range that have turned up over time.
Don't use the body tag to determine production because they were usually built and tagged ahead of assembly and then stored in a 'body bank' until needed.