Very interesting & cool conversion, I didn't realise the Dodge bypass filter were no longer avaliable, Anyone remember the old Frantz bypass filter that used a toilet roll as the filter media, I wonder if you could modify the Dodge housing to accept a toilet roll ?
The LandRover Discovery2 Td5 uses a spin on full flow filter as well as a centrifuge bypass filter ( part number ERR6299 ). I'm pretty sure you machine up an adaptor to accept the centrifuge filter that would fit inside the original Dodge bypass housing . The filter is quite small, about 3" diam & 2" high , but very efficient , it spins at about 30,000 RPM by the action of the drain oil being ejected at angle via small jets. It would be a cool mod as when you shut the engine down you can hear the filter slowing down for about 5 seconds, sounding like a turbine slowing down.