What was the condition of the old plugs? If oil fouled, they should be wet. If they are, it's not an indication of one of the '01 oil burners but of worn rings - I doubt it. Were they normally fouled with black or dark grey powder deposits?
Get on it and ride it for about 1000 miles and then look at the plugs again. This will tell you if the bike is sorted well. Probably just old plugs in there. What brand did you buy and what was the part number? I've always used the Autolites as they're at the local auto store and cheap.
By the way, I didn't think the tank had to be removed for a plug change. They don't on the 97-00 models.
Marc/Atlanta