It is straightforward to get into the 45xx. Start by removing the two screws highlighted in the photo below.
With the screws out of the way you can slide the top and bottom covers back and remove them. (Actually left and right in the photo as it's rotated through 90°)
With them out of the way you can slide the right-hand side panel (as viewed from the front) back a short distance and then lift it clear. Note: The rear panel is integral with the side panel.
With the side panel out of the way you have access to the interior of the thin client
