The non turbo wagon was made from 79-81, and the turbo wagon was made from 81-85. The turbo wasn't put into the coupes and sedans untill 82.
-- Tough to keep straight.
This site has all the info.
http://home.hiwaay.net/~gbf/mbmodels.html
vstech, sounds like you have things undercotrol as far as knowing what to look for. Let us know how it unravels.