Well Greg if you are a P-bass guy you will love the L-1000. It is like a P-bass but much more powerful, with a huge bottom end. It also has the coil-splitter switch with three settings, humbucking/single-coil/bass boost (so-called OMG! mode), and passive bass-cut and treble-cut instead of a tone knob. Very versatile for a one-pickup bass.
I have read that Maple was used as well but those are rare. Maple was usually reserved for the lower-end SB-1 and SB-2 basses.
Rosewood was used too. Most L-1000 necks are 1 11/16" at the nut and are very flat with a tight radius (7.5?). These are a favorite of many players. Probably some went out with 1 5/8" or 1 3/4" as well. All necks had a skunk stripe up to around '83 I think, when they started using the bi-cut neck:
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Only the 1981 basses have slotted pole pieces, so yes they are kind of rare. They change the sound slightly depending on how you line up the slot. To my ears they have more harmonic content than other G&L pickups, but I only have three basses to judge with and my slot-pole is ash/maple so it might just be the wood combo.