help! vt500 exhaust collar stud issue

[HazeVT500]

So I'm trying to take the exhaust off my bike and I'm at an impasse and need some help. The front exhaust flange/collar has one stud that sticks out too far for me to get the flange down between the frame and the stud, and away from the cylinder head. I've tried removing the stud screwing both ways with vice grips. It will turn slightly both ways but not enough to make a difference.

All you modded vt500 riders.. how the heck did you get your pipes off?!
Thanks in advance!