My driveway faces down, will that impact bleeding?

 

If a steep incline, it could. But I found what really makes a difference is making sure the engine is at or very near operating temp when bleeding. Heat makes bubbles and bubbles rise. You also need it to be up to operating temp to make sure the thermostat has opened so you know that the water is circulating and bringing with it any air bubbles that may be in the system.