Comments from a fresh iPad4 WiFi repair.
* Get the assembled panel with the camera bracket and home button. It's worth it.
* These instructions (for the 3?) don't account for the home button cable. It runs along the bottom edge next to the left corner. It's almost impossible to not sever during removal. I have some photos of it I'll try to post when I can figure out how.
* Have light compressed air available to make sure the LCD is clean before reassembling.
* Test fit before pulling off the adhesive strips. I had to do some minor aluminum straightening because of a corner drop, almost blew it had I not test fitted and found this out before sticking it down.
* Test the display and home button before sticking the new glass down, make sure it works, and is all clean.
* I second recommendations for clear tape. Mine was so shattered on the left edge, I had to peel it out in chunks. Tape helped a lot.
* I needed 3 hours for the whole process.
Good luck, and take your time. It can be done!