It is a shame Ron’s pattern maker (and I used him for a few projects myself) had some real problems with some aspects of careless detailing. Pattern corrections by others became often costly. The outer profiles on the sump looked generally ok, but wall thicknesses were the big problem.
Ron told me at the time that the pattern was produced by his pattern maker from copying a repro sump provided by Jack Smith, apparently not Gerhard.
I remember Peter Green telling me about the over-cooling issues associated with the larger K3 sump.
It is my understanding that the one inch thick spacers were used on all earlier K3’s before the introduction of the Hammer Head sumps. Using both would certainly seem overkill!
It isfor this reason Chris why we designed our K/L sump with the deeper / larger N type capacity, adding provision for the larger N sump strainer at the same time. Seemed like a sensible mod.