I am soooo sad; it took me ages to follow all the instructions (not least of my initial obstacles was the fact that what i needed was a Phillips NOT a screwdriver! An anomaly which puzzles me muchly…) & removing the logic-board was a nightmare (basically, it was 'stuck' & broke my spudger, etc) - finally, succeeded in replacing battery & put everything back as-was except now NONE of the screws would stay put, for some reason, except the two @ the bottom of the phone (which one removes prior to opening it up); so plugging it in, to my initial joy, the familiar apple logo showed up…but then disappears. And that's that! So far, nothing moves beyond this start-up point of the apple logo showing up on the screen for a few seconds after plugging it in to the recharger. I hoped at first this was just the new battery recharging, but…? Beforehand, I could use the phone as long as it was plugged in, i.e. the battery wouldn't hold a charge. But now, so far, I can't use it @ all. Does anyone have any suggestions, please?
Thank you, Eric H; after posting I did of course re-open, re-examine, re-align…& have got it now as far as trying to Restore on my computer BUT so far am NOW coming up against a mysterious 'Error 23' (generated from the iTunes/Apple site), which indicates a hardware problem BUT does NOT specify which!? I'm not going to open it again, as I feel with a phone this age, I'm jeopardising/taking a risk with each re-opening. But yes, the battery is charging - now the problem is that I don't have the contents of the phone, & can't seem to get them! Terribly disappointing & meantime I don't have a phone! Will try one last round of attempts to solve/get past this mysterious Error 23, as THAT now seems to be the problem. :(