Early vs. Late dusters

To clarify the rollout of electronic ignition:

1971: Optional, avaliable on 340 and Hemi only.*
1972: Standard on Imperial and Chrysler models, plus all Dodge & Plymouth models equipped w/HP engines. Optional on all other models (including Dodge/Plymouth T-code 440).
1973: Standard across the board.

*Yes, it's the same system used on everything '73-up. Distributor tag numbers:
340 auto - 3438896
340 manual - 3656151
426 auto - 3438893
426 manual - 3438891
the 318 2bbl in my '72 Duster came with EI. I guess it was checked in the option box. I had another '72 Duster with /6, it had points.