(My daughter dropped it on the sidewalk!)
After a failed attempt with plastic opening tools I bought these (Metal Spudger Set). They were slim and strong and got the job done. After a period of gut wrenching fear of failure I succeeded in replacing the screen only to find the “white screen of death” when fired up. A little Googling and I found the old “multi button startup trick” and poof it works like it was new. Dad is a big hero! (Later the cat tried to pull it off the table by the ear buds and I about had a cow)
Muti button startup for Touch 4g is the up volume, home and power until the unit shuts down and starts up to the apple screen (I held these button the whole time). I let it set until it shut itself off and when I turned it back on and it was good! No songs or set-ups were lost.