Great guide. The locking flaps in Steps 18, 21 and 23 are a little hard to decipher in the pictures. I accidentally pulled out the keyboard ribbon cable without unlocking its retaining flap, but I apparently got it in back correctly (after lifting the flap) and didn't break anything because everything works now. This has solved the charging problems I've had for years. I should be able to get a couple more useful years out of this machine now.