I tried heating and folding under the bottom couple of inches of the bumper. It worked ok but it was really lumpy since I was just doing it by hand. I took it for a quick spin and the car seemed more neutral but maybe a slight bit more downforce than stock on the front end. That is probably about right I figure so I put it back in the garage to try and make it look less ugly.
The easiest thing to do since the curve was basically ok was just cut the bottom off and put a strip across the bottom. I used a bit of heat to form up the joint a bit to make it look nicer.
I also used a strip of bumper material to make an air deflector under the radiator.
Now after a quick drive the car seems to drive about right and the fan did not come on at all so it should be getting enough airflow. I will get a picture of it on the ground tomorrow in the daylight. But I did notice when it was parked beside the volt that I have more or less copied the exact profile of the volt. The bumper and hatch angles are almost identical.
