OK, I'm at my wits end on replacing this oring. Done it 3 times and each time the tank boogers up the o ring when I put the pump in. Any of you out there with Aqualines that have a safe fix for this? I'm adverse to start filing away at the tank then wind up with something that wont seal at all. Suggestions welcome. One other thing about these Aqualines, they deform with use and are damned near impossible to put back on the bike, even empty. Took me about an hour to bolt up one tank. I wound up getting a buddy to help and using a long crowbar to force the lower part of the tank to line up with the bolt hole. Of course, after all this, the damned fuel pump o-ring started leaking again once I put in fuel. R&R the tank again and it was no easier the second time around. I've had enough fun throwing tools across the garage and cursing for today, I think I'll have beer. If the tanks werent 1300 bucks I would have tossed em in the dumpster quite a while ago. I know this seems trivial, but it would be a huge goat rope trying to do that out on the trail, and it makes oil changes not so fun. I've been regretting purchasing the tanks ever since I bolted them up the first time. So if you are contemplating getting these tanks, know in advance what you will have to deal with.