I would put in 2 housing. The first could be a courser filter.
You need some silicone grease to lube up the O-ring(s). Never use petrolium jelly or other petrolium, because that swells the O-ring guaranteeing you cannot reuse. Even so, get some O-rings on order too, because if you ever go to change the filter element and the O-ring is bad, you are dead in the water until you get a new O-ring. You can remove an element, but you cannot go without an O-ring.... unless you build in bypassing valves. I put in combo Apollo unions+valves on each side of my filter assembly, but I did not put in a bypass. Also consider adding a boiler tap or two. They can be used to hold a pressure gauge, and they can be used to get water at a point in the system. Or your could just put in pressure gauges. That would let you easily measure pressure drop. Do not filter your outside taps if that is easy enough to implement.
I run a PENTEK-DGD-5005-20 followed by a PENTEK-WP1BB20P in my second and third housing. I left the first housing empty. I did not read your filter element description, but you should only use a polypropolyne filter-- not cellulose.
My 3 filters following my backwashing filters are more than I needed. . My filters looked almost new and new respectively after 13 months. I did not know what to expect, and I felt that overdoing it was OK. Knowing what I know now, I would have put in 2 housings following my backwashing filter.
You might try to leave room for a backwashing filter before the big blue filters in case they clog too quickly. A nice thing about Big Blue filters is that there are many different elements available. It/they may be all you need. Monitoring the filter loading will be a good measure of things.
