Hi - You didn't say which "O Happy Day" but here's the Hawkins version which appears based on the Doddridge/Rimbault version.
FYI: Found it at: http://www.dejanews.com - Do a power search
Set CUR/OLD switch to OLD: [ lyrics | happy | day ]
Oh happy day
Oh happy day ! Oh happy day ! Oh happy day ! happy day, happy day ! Oh happy day ! Oh happy day ! When Jesus washed, oh when he washed When Jesus washed, he whashed the sins away. Oh happy day ! Oh happy day ! He taught me how to watch, fight and pray, fight and pray ! An live rejoicing ev'ry day, ev'ry day ! Oh happy day ! happy day, HAPPY DAY!