I know there is a 1/4" difference in offset of the alternator and PS brackets between the 8V and 16V. I would guess the AC brackets have different offsets too. But as wild said, the blocks are the same, so they should still swap on fine. You will just have to deal with the offset. You could either find the other brackets, or swap the other lower timing belt pulley and water pump pulley, that way the belts will all line up.