I replaced the blades on my Husqvarna Lawn Tractor 48" Deck, 23 Hp, Model# Yth2348 by tipping it on it's side and now the mower looses power when going up the smallest incline? I bled the air out of the transmission per the manual 3X's and still the same. I know tipping the mower on it's side was wrong. I heard it could it be a fuel float. What do you think?

Not the float.
Where you mowing when you had the problem or were you just driving the mower? If you were mowing, then disengage blades and see if it returns to full driving power. If you were just driving, then with it sitting, engage the blades and see if problem recurs. The blades are the bigger load on the engine, your mower will drive around with a little 4HP engine, all the extra power is for the blades and if pulling anything.
Let me know what the test results were, so we can figure out if it is in the carburetor or not.