So, I downloaded........

[Stormstaff]

Ibycus USA.

Sorry for the noobish questions.

Now all I need to do is run the exe file and it'll change/update my maps and then I just need to reload the new maps onto my memory card?

[Boyd]

The .exe will install the maps into Mapsource. IF you don't have mapsource, download and install it first: http://www.gpsfiledepot.com/tutorials/how-to-install-mapsource-if-it-didnt-come-with-your-gps/

In mapsource, select the portions of the map you want to transfer to your GPS, connect either the GPS itself or a memory card reader, and use the transfer menu to send it. I don't recall, but I suspect the entire ibycus US map may be too large to install the whole thing.