M-code and 383 A-body plug wire question

The B-body HP driver’s side manifold dumps right at the back so all of the plug wires go underneath from the front, so the 383/440 B-body HP (and the reproduction) valve covers would only have plug wire provisions on the passenger side. The low performance big block B bodies have a different set of manifolds where the driver’s side has plug wire clips. I would just like to know how the big block A-bodies are different. Does anybody have an unrestored car they could share with me?