There is one part that you'll need for a whole Micro E, and that's a spacer that sits directly over the battery case and helps smooth the transition to the body. It's 100% cosmetic though, so you don't actually NEED one. Although, come to think of it, it probably gives you some protection for the wires in the frame.
From what I can recall after having an E-mag in my hand 2-3 months ago There is nothing special about Micro E lowers except for the milling on the battery case.
Rainman here on MCB did my millwork.
Do you have your micro body yet? I ended up with an extra raw body after all this was said and done.
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