Updating garmin 760
I looked on this site and it looked like my 760 would support 4GB SD cards.My nuvi 750 should update to SD identically to your 760 and at the last update (2013.40), I was able to install all of North America to a 4GB SD card.
In fact, I think a 2GB SD card can actually use about 1.8GB so that explains your 2GB less-than-all-North_America problem. Your problem may have occurred due to using Garmin Express.
On the other hand, you could bypass a repeat 2013.40 installation since 2014.10 is due out very soon, possibly even next Tuesday--and with your 4GB card and Garmin Map Updater, you should have no problem with the full map update to the 4GB SD. *map file size for 2013.40 with all of North America: gmapsup1is 1,926,368KB (1.83 GB or 1,972,600,832 bytes) and there are a few other tiny files needed as well.
If the maps are installed to an SD card, what file elements originally located on the GPS unit are now on the SD?
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