I have ramhorn manifolds on my truck now {with the rack and pinion ) but on another truck I built (with stock steering box) I used 1955-1956 265 manifolds . They go up from the exhaust ports (like the ramhorns) but the "dump" was between the 1st and 3rd exhaust ports - which cleared the steering box . I think there was a similar manifold used on some '80's chevy cars also.