Here is what I would do. Lower the top all the way and disconnect the 2 bottom lines. Then get a large syringe (vet type) and push the fluid from one side to the other into a container half filled with oil to prevent it from sucking air back in. Reconnect the two bottom lines and cycle the top up and down (watch the fluid level). I don't think you will need to do anything with the top lines as the air will automatically rise in the cylinder and ultimately be pushed into the pump. I did something similar a month ago and I have no/minimal air in all the lines.