I had my defender fitted with some temperature logging device by a Scandinavian filter company, we concluded the Tdi does produce high enough temperatures, at the rough fitment point of the filter, to only require a simple filter system. So no need for extra dosing or post turbo fuel injection.
The filter was £1800 but that was literally a filter in a box, no guarantee on making the VOSA test for emissions to reclasify it, and the sizing IIRC, was around 8" dia by 18" long - probably a bit too tight for a 90 but not for a 110. I have never received a proper engineering drawing of the filter, nor a picture. the informtation did come from the manufacturers though.
So, I have decided to fit a V8 to my hardtop, the family 110 is going through reclassification (we hope)
A friend of mine has an ex TD hardtop, now with a different body and 3.3ltr Mazda diesel engine, and he is classed as exempt. What justice is there in that? Where a vehicle with a huge diesel, that is a commercial, is exempt whereas my pukka hardtop with smaller Tdi isn't? I echo everything about his being a farce, frankly I feel terribly hard done by.