tint removal

I get the tint warm, such as sitting it in the sun or I use a heat gun, then a nice new razor blade and start peeling trying to get as much as I can in one piece. Be careful of the defroster lines in the back window, and get some towels and or rags and some acetone or alcohol for cleaning any residue left behind.
on the side windows, if the tint isnt completly dried out,pull tint down off window,but leave on the botton two inches of the window,and razerblade the glue off.the tint will stop the glue from going into the door felts preventing a big mess.
ammonia and heat are the 2 best ways. i use ammonia and a black trash bag to keep the heat in with the car out in the sun,.
Yes Black Trash Bag Let It Get Warm ,turn On Window Defroster To Heat It Up ,but Watch Out The Razor Will Cut The Defroster Lines And They Will No Longer Work And If You Re-tint It ,the Lines Will Look Like Crap Use Formula 409 Or Ammonia,steelwool pad no sos pads fine steel wool (home depot)soft scotch brite pad let the chemicals disolve glue ,glue will make huge mess get glue off before you roll windows down (electric wont come back up )GOOOOOD LUK
The best way to get tint removed from the back window with a defroster is what we call the "sweat method" Long as the window tint is not totally bubbled, this method works.

Remove the back seat and back package tray

1 black trash bag and cut the bottom and one side out.

Wet down the outside of the back window and smooth all bubbles out

Trim the trash bag out just a little bit bigger than the window.

Spray either 409 or Simple Green throughly on the inside of the window

Place black trash bag on the inside and remove all air bubbles and place car in direct sunlight.

100 deg day will take about 15 mins and 70 deg day about 30 to 40 mins.

DO NOT let the 409 or Simple Green dry or you will have to re-wet the window.

After the black bag has set the desired time, pick at one corner and the majority of the tint and glue will remove itself.

Spray deliuted with water dish washing deturgent (orange Palmolive) on the glass and use a chore boy or blue scrub pad (green is too harsh) and scrub down the defroster lines and outer black boarder to remove any additional adhesive.

Side windows, always use plenty of single edge razor blades as they dull out pretty easy removing old tint and can leave small scratches if you are not careful.

How do I know about this? I use to tint windows full time and still do from time to time.