According to Airstream there aren't any service manuals for Argosy trailers, but I have a '75 Airstream service manual. Looking at the water distribution system for 23 & 25 ft '75 Airstreams, it shows the water inlet, then the regulator assembly a little inboard of the inlet with a checkvalve listed as part of the regulator assembly. There is no indication that the drawing is to scale, but it looks like it's within 2' of the inlet.
Il Carriaggio — 1975 Argosy 24 | Il Progetto — 1976 Argosy 28 Center Bath | WBCCI# 15566
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