A good friend of mine has designed and developed this alternative back plate. It is 3D printed and allows the USB power cable to attach whilst keeping the back enclosed to the elements.
I have one and can vouch for how great it is. See the link below for his eBay site and also some further pictures. Let me know if you have any questions and I will get the answers for you.
http://www.ebay.co.uk/itm/132229418702?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
I have one and can vouch for how great it is. See the link below for his eBay site and also some further pictures. Let me know if you have any questions and I will get the answers for you.
http://www.ebay.co.uk/itm/132229418702?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649