I read an article on this and it says when you use metal between the meter and the panel. When you do this you parallel the neutral between the panel and the meter. Does this also mean that when you use rigid for the riser it is paralleled as well? I researched this and found that you can not screw a pvc fitting in a threaded metal hub. So you can use a short metal nipple in the hub with a female adapter then take the pvc to the meter. You would have to do the same if you use a rigid pvc riser. The nipples are grounded by the meter or the panel.