The United States international said: "Being left out for the final was one of biggest disappointments of career.
"It was quite frustrating and a difficult pill to swallow.
"But that's behind me and I think that has made me a stronger goalkeeper and a stronger person.
"If we can get back there to Wembley again, that would be great."
Guzan admitted: "It would definitely be good to back there and play. But that's a long way off.
"We've got a massive game on Tuesday where we have to take care of business first with.
"For me, it is just a case of one game at a time and keep moving forward.
"We will try to get the win and into the hat for the next round and if we can do that it will be a job well done."