I had the precut replacement adhesive tape kit. Unfortunately it did not come with instructions on how to and in what order to remove the plastic. I ended up trying to get the adhesive tape lay in properly. I highly recommend the 4mm TESA tape.
I saw in some “How To”videos, the repair shop had expensive heating pads to assist in screen removal. If I ever find myself making a similar repair to an iPad of iPhone, I’m going to try using a heating pad I have for my back. Set it to high and let the iPad/iPhone set on it screen down for 15 minutes or so. Should do the trick.
When I purchased a new replacement battery, it came with a suction cup. That cheap cup wasn’t able to hold on the screen. luckily I had a set of heavy duty suction cups when I made a repair on my iMac. I recommend investing in the heavy duty cups.
These provide an excellent vacuum seal and leverage to lift the screen. Be careful and make sure you soften up the adhesive or you will crack the screen.
I just found the instructions on how to install the seals AFTER I was completed and had to figure it out. Maybe, just maybe you should link this somewhere on the guild instead of buried in a comment. Just a thought.