I've anatomized my dead 1965 Ventures II (German Carve) pickup.
The construction is different from the pickups with pole pieces (great thread here: http://www.mosriteforum.com/forum/viewtopic.php?f=20&t=4319), as the two magnets are inside the bobbin (actually, they form the bobbin), separated with a small piece of maple. No potting, only a little glue, bobbin and coil held together with adhesive tape (paper).
Here's a picture:

Does somebody know the construction of a Ventures II slab body pickup? Perhaps the same as here, only with less windings?
Cheers, Max