Thanks for sharing the results. If I may ask, why the BF1212?
Not a bad filter and certainly a commonly available model, but isn't the BF1268 (or Cat 175-2949, Donaldson P553201, Donaldson P550847, etc) regarded as a better first pass filter? I think the four I listed are all synthetic media. As far as I can find, all similar flow specs, appropriate for a suction side primary.
I think the specs on a BF1212 are 4/20 micron and 4/13 for the BF1268. BF1268 and Donaldson P550847 are <$20 at my local dealer.
Not trying to be critical, just in it to learn. I recently went through filter trials for our truck. The FASS pump would loose prime when parked. Ultimately found standpipe Filter/WS units as the primary (BF1258, Donaldson P551001, etc) were the problem. BF1212 (no standpipe) solved the issue but I would like to catch as much crud there as I can without choking the pump, rather than passing it to either of the two downstream filters.
I'm not really that familiar with sensitivity of 7.3 HPOP and HEUI sensitivity to clean fuel. I worked in the factory that made the 6.0 HEUI and was aware that it had...issues.