1966 plymouth fury VIP power steering question

Hi all,

i bought the car a few months ago and slowly working my way through the varies issues. Started on the power steering leak(s) last week. Ive replaced the pressure hose as that was weeping and just degreased everything and will try to isolate the leak over the coming days.

My question at this time is, is the power steering system vented or non-vented? the cap on the pump says vented. However im not convinced its the correct cap as its very loose and rattles around when running and doesnt seem quite right..

Thanks!
Author: grimley