no you only run it to one of the hoses - the one with the pcv valve (passenger side on EFI 5L). Leave the other hose as is.
Essentially all you are doing is cutting the hose between the PCV valve and a ported vacuum (throttle body or carb fitting) and fitting the catch can between the two ends of the hose.
I've drawn up a crude schematic below. Hope it makes some sense
Crankcase fumes are drawn out of the engine with the aid of engine vacuum from the passenger side rocker cover (via the PCV valve). The PCV valve is basically a one way valve with a very basic integrated oil separator. The fumes are drawn back into the carby or throttle body and consumed by the engine through the intake. Obviously if you are pulling air out of the crankcase, you need a vent to allow fresh air back in. So the drivers side rocker cover outlet acts as a vent. It pulls air in from the atmosphere via the filter side of the throttle body or through a fibre glass filter in the air cleaner housing on the carb engine. The catch can is mounted in the middle of the PCV hose side, so that it catches any oil that gets picked up before it gets pulled (by engine vacuum) back into the intake.