well first off i hate the dashpot myslef, i noticed that it holds it open a bit sometimes so i took it off lol and just left the long screw there.
also the the test u did on ur TPS is right, as long as u measured the top 2 terminals, it should have continuity, and when u open the throttle it should read infinant. in respect to the throttle opener, first set ur TPS once done and set with the .020 feel guage and .030 guage, set the throttle opener to the point just after the meter reads infaniant on the top 2 terminals, this should give u a base line to tinker
hope this somewhat helps