Early-A 225 Slant Six Headers
If you have manual steering, then the Clifforrd short tubes will fit. The front tubes require shortening with PS. These are a truck version of the Clifford shorties. The front 3 are identical to the passenger ones; the rears point down rather than back with the passenger car headers. This style uses a unique Y Pipe to connect the pair.
Otherwise to use headers and PS, the only option is to use Clifford long tubes (out of production for a good long time now) or repros from Aussie Speed (I think it is).
I was mocking both up to see how everything fit with a slant 79 AC bracket.