you can use the older style wp housing with the outlet on the driver side ....but just sayin ....I always use the later style one with the outlet on the passenger side on A-bodies.
it makes more sense to have the outlet on the passenger side because there is more room over there and you don't have the oil filter getting in the way (you will be happy about that when you change the oil :-? ) the other reason I like the pass. side outlet is because you can use a Small block radiator....which is cheaper and easier to work with.
on my 440 car I have the outlet on the pass. side and I went to auto zone and ordered a new radiator for a 73 duster 340....26" inch radiator .....bolts up in the A-body like it belongs there ....has outlet on pass. side so the lower hose is not crowded in there and the SB radiator does a great job with cooling, even in heavy Denver traffic....I drove my 72 with a 440 as my daily driver for almost 3 years and it went everywhere.
I don't have newer cars so my darts get driven, so they have to endure quite a bit. :D