Thanks again, guys. I took a few minutes last night to start the sorting, and, once I actually held some pieces in my hands for contrast, the differences you told me about became very clear.
I hope to continue the job tonight.
Once thing I have rediscovered is an impression I first noticed years ago but had forgotten: the ends of the bottom flanges of rails on MARX track seem to all spread. the end of each rail looks like a fan after it has been assembled/disassembled a few times. I wonder if that effect is because of the pins--which seem fatter than the Lionel--or less stout rail stock. Lionel does it, too, but not as consistently or as wide.
