exhaust troubles on 66 barracuda

Got my 66 barracuda ready for exhaust, so I thought. I have built and installed 68 340 and used original exhaust manifolds. Took it in to get exhaust and was told passenger side was too tight to hook up. oil filter is in way. Is the 273 oil filter in a different spot on the motor? So now I need to find a manifold that exits out the rear of manifold instead of the middle but all I see is middle exits except on the big block manifolds. I know putting a 340 in a early A is done all the time, what am I missing?