x2, might as well replace the bearings and definitely the seals while you're at it. If you don't, Murphy will make the bearings wear out a month from now!! Also, go for the better bearings, they last longer than the cheap-o ones!! And keep in mind there will be more stress on the bearings with the wider axle, so they will be needing replacement more frequently...but they're not expensive and not hard to do.
If you JUST did the bearings recently, you could probably get away with just re-doing the seals. I would do the seals again at the very least. Coat the lips in grease, generously, so that they don't get damaged during install. They keep your bearings happy!!