I believe all that was retooled was the outer hull. Internally, it would be the same as the 1st design kit, that is, the WTC is built permanently inside the lower hull half. Engel's Lafayette kit splits similar to Robbe's U-47, however, uses a bayonet locking ring rather that that long a++ screw to hold it together. I have about 26 hours on my Lafayette now, and not a hint of a leak. If you need more info on this, let me know and I will email you some pictures.
The complete lack of evidence is the surest sign that the conspiracy is working.