Lambros, I had the same problem, some older cmc, and fiberfab bodies have 3/4" less clearance on the drivers side. I took my chrome "mangel" wheel to "stockton wheel Co." conveniently in stockton california ( other good wheel houses can do this).. I explained my dilema, and they removed the center of the rim, and offset it 5/8 of anm inch.....then they rewelded the center in with the new offset. This did not damage the chromed finish, as they weld the back side. Now both wheels have exactly the same clearance from the fenders. Of course I can't rotate my tires because of this one weird offset rim, but I consider that an inconsequential result. All wheels "Look" perfect, and the problem is cured.
The second consequence is that I cannot ever change my rims to any other custom rim, unless it is a 2-piece rim where i could do the same trick to it. But I like the wide 5 chromes, and porsche nipple hubcaps that I'm using anyway.
Gclarke "The Vacaville Guy"