Steering box help

Yes the fwd port is the return. It is a removable aluminum fitting w 2 bolts. You could swap in one from a later box to match the smaller (recall) hose size of the Saginaw pump. Similarly, you can swap the HP port (maybe whole top block, forget). As I recall, the HP fitting at the pump varied, being inverted flare in TRW pump, SAE flare in Federal ("Chrysler") pump (your 1968 I think), and O-ring in later Saginaw pump, but don't quote me. You must be doing a custom hose w AN fittings. I would stick w/ the O-ring fitting since seals best. Your 1968 HP hose likely changed sizes via an Inline crimped coupler.