you will have no issues. the EA500d is an excellent unit that offers 500w of continuous power rather then peak power like a lot of 500w units.
you will have no issues with power connections, i have two 6+2 connectors running to my GTX460
simply run the single 6-pin power connector to the GTX460
then use the 6+2, the two pins simply break off and hang to the side (see the image)