The CM400E is a manual transmission model, kickstart only, spoked wheels, and drum front brake. The CM400 and 450 A models have the automatic transmission, disk front brakes, electric start, and comstar wheels. Swapping an automatic engine into a manual frame is somewhat more than a simple bolt in operation.
I would suggest that you start by comparing the serial number on your title with that stamped on the identification plate on the frame neck below the handlebars.
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