G'day
My car was originally a column shift,but been converted to t-bar auto,but i still use the economy/power switch in the dash so i have the unused switch for economy near the auto transmission shifter.
Question. Has anyone out there ever tried to wire up the two rear windows(would have to install the electric motors,etc) utilising the one switch?

hmm interesting, should probably work I guess, but couple questions why not just do a full window conversion using the intended method?
And are you aware that you'd need to change the switch to a rocker style switch or atleast something with 3 points, as the economy button would only allow two of the 3 positions you need, (down) (up) and (standing position).