Not to start a debate on the pros and cons of gascolators but what you are proposing makes no sense.
The purpose of a gascolator is to collect water and contaminants and should be installed in the lowest point of the fuel system.
By installing it in the wing root, you are effectively mounting it approx 4 inches above the lowest point in the system and right next to your fuel tank drains.
These drains are installed at the lowest point in the tank and collect/drain water and contaminants if any.
Mounting a gascolator in the wing root space is counter productive in more than one way. It is a tight space where elbows and sharp turns in the fuel line are needed to connect the in- and outlets of the gascolator. Such an installation on the suction side of the fuel system may contribute to future issues like vapor lock etc. Adding a shut off valve for serviceability is yet another couple of fittings that need space.
Not sure what your engine configuration will look like (carbureted or fuel injected). Consider an inline filter instead of a gascolator, there is simply no good place or good reason to install a gascolator on a low wing aircraft.
1, In Canada, you will not get a final inspection pass without a gascolator installed, carbureted or injected.
2, Since I must have a gascolator, I chose the Andair because it also has a great filter (cleanable mesh) which is sufficiently fine (7O micron) for my fuel injection pump.
3, The gascolator works good in the wing root because:
A, it must be upstream of the aux boost pump and this location this also eliminates the need for the big heavy filter normally installed inside the cockpit where it is more difficult to get at for cleaning.
B, It is in a cooler environment than in the engine compartment where slow moving fuel can pick up heat.
C, The tank sumps are the lowest point in the fuel system and this is where the majority of water will collected and be removed, not at the gascolator.
D, The Andair gascolator does not need to be at the low point to collect water in a system of tubes where the fuel is constantly flowing. It collects water due to its design.
E, it is easy to make the gascolator sump-able in the wing root. In Some FWF installations, the lower cowl needs to be removed to sump the gascolator.
F. If one gascolator/filter is good, two are better. If one was to get contaminated, I can switch to the other tank complete with its own filter.
So far it works great for me. 120+hrs. YMMV
Bevan.