Why was Willy happy before talking to Howard?

Willy leaves for work in high spirits that morning. As Linda tells Biff, it's just like the old days. Willy is feeling on top of the world because of Happy and Biff's "Florida idea," their plan to open a sporting goods business. Happy got the idea when he was in Florida, hence the name, and Willy is pretty enthusiastic about it. He's pleased because, at long last, it seems that his sons are going out into the world and staking their claim just as he always hoped they would. Biff's hoping to obtain a business loan for the new venture and he and Happy are planning to discuss the details with Willy that evening at Frank's Chop House.
So Willy has a definite spring in his step when he heads off that morning for his meeting with Howard. Unfortunately, things go badly and Howard ends up effectively firing Willy. Worse is to come at the Chop House that evening when it's revealed that Biff didn't get the projected business loan for the "Florida idea" after all. Willy's happiness as he left the house that morning to see Howard was based on an illusion, just like his whole life.