I've dug out the info I had tucked away and this appears to be the situation (there was discussion about it a long time ago on another forum)
The first of the Pre-EB Sabres (1979 to circa 1983)
*Exposed pole pieces on both pickups (magnets visible and appearance the same as on the 'Ray)
*The neck p/up is smaller than the bridge p/up and, in turn, the bridge p/up is smaller than the 'Ray p/up.
The second of the Pre-EB Sabres (circa 1983 to 1984)
*Again, the front is smaller than the bridge and both smaller than the 'Ray p/up.
*Both p/ups are the same size as the earlier Sabres but now sealed. The magnets are not visible.
*The number of poles on the neck p/up are increased. In the pic below, the p/up on the left is the insides of a sealed neck p/up. The p/up on the right is from a 'Ray and is used mainly to show the difference in the pole magnets.