Just out of curiosity, why are you considering a DIY upgrade route, instead of just selling your existing device (as used) and buying a Razr HD Maxx (used)?
Current market rate for a used Droid Razr HD is ~$350 - $400. Current market rate for a Droid Razr HD Maxx is ~$450 - $500.
The problem with a DIY upgrade is that you can't get warranty support / replacement in case anything goes wrong. And if something does go wrong with your device, it is likely a problem that cannot be easily repaired as an inexpensive DIY repair (e.g. the likely problems will be a motherboard dying, or a screen that needs replacing).
I think the rationale behind a DIY upgrade is because we have the Razr HD in Canada operating on 2600MHz GSM LTE and the Verizon Droid Razr Maxx HD is CDMA LTE only and only a USA item. Other then the battery and rear cover the Droid Razr Maxx HD is useless for LTE speeds in Canada or elsewhere.
I know that's why I'm looking for an upgrade kit or used/broken Maxx HD phone.
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