I have just done this after trying other methods suggested on the net.
The simplest way was to warm the tape itself with a hair dryer then scrape the tape off with a knife or plastic card. Soak the residue on the glass in cooking oil on a piece of kitchen roll. It seemed to dissolve the remaining glue very quickly.
then wash off with washup liquid.
No harmful chemicals or expensive glue removers involved. Best not to waste your best olive oil on it though!
Remove duct tape adhesive with Goo-Gone or Goof-Off.
Most sensible people don't, because the tape is then useless.
Goof Off or Goo Gone.
Windex. paper towels. Small scraper. Spray Windex let set a minute. try scraping it off with the scraper, add windex as needed. Wipe clean with a paper towel.
The adhesive tape left a sticky residue on the glass.
Warm the tape with a hair dryer or heat gun.When the adhesive is warm it comes off easier.
oil
Nail varnish remover, turpentine or lighter fluid are all very good at removing this but make sure you open windows/ doors ect when cleaning with these.
break the glass and then duck tape the hole and every thing will be fine. PS: make the duct tape tight so water does not leak into the car like it did with me.
Remove the decorative cover to your 1997 VW tape player. Remove the tape player retaining screws. Remove the wiring harness from the back of the tape player.
Remove the tape player decorative cover. Remove the tape player retaining screws. Remove the wiring harness from the back of the tape player. Reverse the process to install the new tape player.
with a fiber glass piece
Your local auto glass shop will have a replacement glass that goes on with double sided tape, it even has the "objects are closer" on it. You just carefully remove the old glass and stick on the new glass
Soak the paper with spirit ( ethyl alcohol) and then remove the sticky tape.
Remove duct tape adhesive with Goo-Gone or Goof-Off.
Duct tape won't remove plantar warts.
Buy some "Goo Gone" slather it on and let it sit over night and then rub with a paper towel, you may have to repeat but I have had good luck with this.