Coolant filter setup for CUCV - picking the best option

Friends:
Having just replaced the radiator, heater core, hoses and thermostat in my M1009 I now turn to installing a coolant filter to keep the system as clean as possible. Despite flushing, who knows what crud there is piled up inside the engine block ready to infect the coolant system with each rotation of the water pump, not to mention the silica (sand) in the coolant itself.
I have obtained the NAPA coolant filter setup, and it’s ready to install.
It looks to me like there are three basic options. The first two I got from SS, and Option #3 from a Google search. They are described below, plus in the picture, attached. I am trying to figure out the best configuration, and would appreciate the benefit of your real-life experience.
Anyway the three options are as follows:
Option #1: “Series”. In this setup the coolant filter taps into the outbound line from the radiator to the heater core, both “in” and “out” sides of the filter. Advantage: All coolant gets filtered all the time. Disadvantage: Scenario where filter becomes clogged blocking entire system. Effective but potentially risky.
Option #2: “Parallel”. In this setup the “in” line to the coolant filter taps into the outbound line from the radiator to the heater core, and the “out” line taps into the return hose going to the engine block. Advantage: If there is a filter blockage, the cooling system will continue to function as the coolant will follow the path of least resistance. Disadvantage: only some of the coolant gets filtered each time.
Option 3: “Overflow”. In this setup the in line to the coolant filter taps into the outbound line to the heater core, and the “out” line taps into the tube between the radiator and the coolant overflow reservoir. I guess one variant of this might be to tap the coolant filter “in” to the return line from the heater core. Advantage: If there is a filter blockage, the cooling system will continue to function as the coolant will follow the path of least resistance. Disadvantage: Uncertainty in my mind regarding how effective this might work. I know it’s a closed system, but suspect different factors are in play tapping into the coolant overflow line.
Any comments appreciated before I start pounding away!
Gloaf

I use option #2 on my deuce, it filters very well and if it does get restricted it won't block anything. Just my thought.

I don't see any problem with option #1, even if the filter does become plugged... Not all of the coolant is flowing through the heater core, and there have been many instance of plugged heater cores not causing any issues other than a lack of heat in the cab.

Coolant filters were never designed to flow the entire coolant system through them.
Tap into the block (pressure side of the water pump) and connect the "out" of the filter back into the suction side of the radiator or radiator side of the heater hose.
Your coolant filter should be running about 3/8" hose to and from it. Yes, it does filter the coolant and clean out debris BUT, the main job of a coolant filter is the SSLLOOWW release of the SCA packet inside it. That is what helps keep the chemical balance within the cooling system.
Using a coolant filter that has an SCA charge in it is then dependent on the coolant you run in the system. The "old style" green coolant that id DIESEL approved should have SCA's in it to start with. As these chemicals are depleted, the packet in the filter dissolves and maintains the proper levels.
If you choose the run the Extended Life coolant, DO NOT ADD "SCA's to it! so you have to choose a coolant filter that does not have a chemical charge.
For our fire truck fleet we have moved to the 50/50 pre-mixed Extended life coolant. This fixes 2 things; 1, firemen don't add tap water with all it's impurities. 2, the system if filled with the correct mix right from the go.
Even if you chose to use traditional coolant, buy the pre-mix! your cooling system will love you for it!