I removed mine without losing any of the defogger lines.....

I'm not sure if this is easiest or best way, but it worked incredibly well for me, so here it goes.

I used one of those curtain steamers, they're real cheap...like $10-20 at Wal-Mart, I think the one I bought was made by Oster or something. Anyway, I just made a small slit in the tint w/a razor blade as a starting point. Then I just steamed the tint a ton, especially the area where I immediately peeling. It came right off, just like that.

There was some glue residue left behind in a few spots, but a good cleaner like Industrial Strength Windex took care of that.