Believe the 67s used a kinda "bread loaf" shaped canister, as opposed to the later "coffee can" style. I have one of the "bread loaf" shape and it has two 90 degree fittings, one about 3/16" diameter and one about 1/16" diameter. Neither has a check valve, as on my later "coffee can" ones.
Unsure if it should have a check valve on one connection, or if this style can was just an open path.