Ok, so not strictly Manchester, but The Magnet in Oldham was a great mid week venue in approx 1974/5. If memory serves me right it was on a Wednesday but cannot remember who the dj's were.
Seriously for me the premier Manchester venue in the 70's was the Pendelum. Cellar club with superb atmosphere, walls dripping with condensation, Newcastle Brown behind the bar and a young Richard Searling in attendance ( I think), friday nights and a perfect warm up to the Mecca/Casino. Happy days!!!