Good question. I think it would be very hard to remove and replace the o-rings with the alternator in place. I won't know until I put the alternator back in. With the alternator out you can see your work. Even if you could access the single e-torx bolt that holds the lines on while the alternator was still in, you would be working completely blind. It will take a gasket hook tool to take the old o-rings off. If that is indeed the source of your leak, once the alternator is out it would take 15 minutes to replace them. One bolt to remove, pull the lines loose, replace o-rings, put lines back in, and replace the bolt.