The bolt spacing along the row the bolts are located in (from front of head to back end of head) is identical on both heads, because there is only one head, and it faces one direction on the driver's side and the other direction on the passenger side.
What is different is the spacing of the bolts side-to-side between the intake manifold and the exhaust side. The bolts are offset toward the exhaust side, not in the center. So... if you tried to put a Corvette driver's side valve cover on on the passenger side of the F-Body, with the notch for the alternator in the front, the bolt holes won't line up.
