Pull the battery out, and there are 2 screws in the back, after removing those the plate will come out, you have to fight with it a little till you get used to it. The mechbox will come out right behind it with ease.
The mechbox itself is the easiest Iv'e ever worked on. Just take out all the screws and remember where they go, slide off the top metal support thing and you're in. from there it's just like any other mechbox.
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