I used only 6 the first time and it was perfect and i used 6.5 this time and had to let some out because it was over the line and yes I changed the oil filter both times.
5.5, check it... then add 1/2 to 1 qt more but keep 1 or 1/2-bottle whatever you have left around for topping it up after a bit. We do use some oil periodically.