hey,

well i decided to remove my tint yesterday and all i used was a butter knife to peel up a corner and it peeled straight off but then i thought it was a bit too easy and realised it was made up of two layers. doh. the second layer flakes so i did a search and came up with this -

http://doityourself.com/auto/automotivetintremoval.htm

it makes sense, dont know about the ammonia though. but yeah im gonna try it today and i'll let ya know how i go.

hope this helps.