There are rubber strips on each side of the machine that run front to back. Start at one end and peel/pry these strips off (they are flexible). There is a plastic strip under the rubber that slides toward the front. The head of the machine must be hinged open to allow room for the plastic strips to be removed. Push the strips toward the front - a gentle thump in the direction on the end of the strip will help. Then lift top cover off.
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