Agree with "nweeks" on it being impossible not to break the foam. However, I reinstalled without the foam. Since the earpiece is wrapped in the ribbon cable and it's also very securely contained in the recess, I can't see the foam adding a ton of value. My phone worked fine after I reused the earpiece without any new foam.
Maybe it's just me, but I had a hard time getting the earpiece out as it was wrapped in the ribbon cable and also had adhesive on it. Folks should be super careful here. Ultimately I torn the cable, but since I was replacing it anyway, it was ok. It really had me worried for a bit.
Step 26 cause me great pain as well. I couldn't get it loose with the plastic spudgers. I had to break out a tiny metal screwdriver. I was so paranoid that I was going to break the part or the clip. The trick is to get under the clip's "fingers" that fasten it on the sides. The issue is that even my small my plastic spudger was too big to fit in the available space. Ultimately I got it to work with a micro flathead screwdriver, but it wasn't without serious concern.
I agree that the SIM card should be removed before you even start. After I completed this repair (waiting until this step to remove the SIM), the SIM card and holders won't go flush with the side of the phone anymore. The phone still works and everything else is fine, it's just annoying that I have a SIM holder sticking out about 1mm. I'm not certain this step caused this, but I'm just letting folks know that I agree with jmaelzer.