Tire hitting fender

Right, so if they're standard that means they're either a 0 or +6 offset. And the 10" SBP drums means you have at least a 1/2" extra space because the track width is more than a 1/2" narrower going from SBP drums to BBP disks. If the OP had and extra 1/2" of backspace to make up for the change in track width he'd be set.
Does he have 14x7's on the front? He needs 6's. Of the few photos I have seen of the issue the rim sits out too far. I have yet seen a photo of what part of the tire rubs the fender. May be there is a photo buried in 4 pages of posts. I bet that tire on a stock offset wheel wouldn't be an issue but I am just guessing. (as we all are)