Hello Brian,
I have never seen or used a E200 before, however many of the google and ebay hits refer to it as a "POWER SUPPLY NODE E/F CLASS" part # 641227-001 which leads me to believe the parts and instructions might be interchangeable between a F200 and E200, but I don't know that for a fact.
The docs for the F200 show that the battery is located inside the power supply and is accessible by removing the power supply from the chassis, then removing the 2 screws with a #1 philips screwdriver, and opening a trap door on the top.
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