Don't know if there have been any topics posted about this, but i was wondering if the ignition keyswitch system and doorlocks can be interchanged between the 240, 260, or 280's. I see a bunch of sets that are off of 280's and mostly 280's at junk yards, but i have a 240 so BLEH. appreciate the replies, take care, thanks.

Yes. I bought a complete NOS set of locks with matching keys off of eBay - from a member of this club. They're actually the later 280Z style keys. The grooves are different. Other than the key itself everything is identical and can be replaced very easily. I didn't bother with the break-off theft protection bolts for the ignition lock as it took me just a couple of minutes with a dremel tool to notch the originals enough for them to be backed out with a flat bladed screw driver. You'll presumably need to do the same sort of thing if you intend to pull them yourself at a yard.