Hi, on the Open Sprinkler Pi web pages it mentions the use of a nano wifi dongle and shows this in several photos of the standard Pi version. For the plus version, does the enclosure include holes for the USB slots thus allowing a slightly larger wifi dongle to be used? Or will only a nano dongle fit?
The OSPi user manual has a few more pictures which will probably give you a better idea: http://rayshobby.net/docs/ospi14_manual.pdf
I would say it’s pretty difficult to fit anything larger than the nano-size dongle. However, you can always modify the case, using a dremel to open a cutout or something, to fit a larger dongle.