General Motors is planning on adding a third shift to a plant in Flint Michigan later this summer. The 750 jobs will be filled by laid-off GM employees. The jobs will be making the Chevrolet Silverado and GMC Sierra heavy-duty pickups to meet what GM is calling “an expected increase in demand”. Where is this demand for big trucks with rotten gas mileage (as gas prices soar)? GM foresees growth in housing construction, which will increaseread more…