In common with everyone else, the tabs broke off immediately (brittle with age). I rested the phone on a hot water bottle (no microwave here) for a few minutes. Managed to get some fishing line under the battery at the charger / home button end and then gradually (had to keep reheating it) managed the pull the line backwards and forwards, slowly working my way down the battery. And out it popped. Remaining glue came off with a bit of scraping with my finger nail. Probably took about 15 mins to sort this stage out.

What a fantastic guide. I've never done anything like this, other than increasing RAM, but 2 hours later and I've got a new hard disc in place and operating. The added comments help clarify enormously. And the tips to use pots and cardboard press-in's for the screws were invaluable. True to form, stage 16/17 was the hardest bit (a plastic lollipop stick helped me) followed, bizarly, by getting the screws back into the battery compartment - two are still a bit squint, but the battery fitted so no matter. Thanks again ifixit!