ps I know some people posting above managed to replace battery in fewer steps but one advantage of complete dis-assembly is that you get to use air-duster to blow out dust from everywhere, especially fans and all nooks and crannies….and to clean gunk off boards with isopropyl alcohol….so not only does one end up with a new battery but also a cleaned out, better ventilated machine….

A really good guide - thanks! Not for the faint-hearted but process went smoothly - magnetic project mat, good torx, pentalobe screwdrivers and plenty of take away food containers and post-it notes for labelling parts associated with each step really helped when it came to reversing process. It’s quite easy to select wrong screwdriver (torx vs pentalobe) so I got into habit of carefully trying both for best possible fit before committing to unscrewing/screwing the tiny bolts…When I got down to the battery the removal fluid supplied with my new battery worked very well if left for a minute - need to be patient working space for next drops of adhesive dissolving fluid. Did the new battery charge/discharge process and now MacBook Pro has a new lease of life…trackpad works again, no bulge in case and v good battery life….but I know that very many people would discard a 6 year old top-of-range MBP laptop simply because of battery replacement issues…it’s really not good enough Apple!

Whole process took about 3 hours but went well as I had all required tools and some prior experience.

Agree that most difficult part is ensuring that all ribbon cables and connectors are outside logic board

and not underneath it during reinstallation….the antenna connectors were also a bit tricky - I use a binocular

magnifier on my reading glasses and strong work light. Also had air duster can on hand and isopropyl alcohol and cotton buds to clean

up interior of mac along the way - quite a lot of dust inside. Although mac sounds better now with replacement right

speaker it is still not perfect…I wonder whether audio drivers are also implicated in my original problem (fuzzy distortion

on right speaker especially of lower frequencies)…..

Replacement went well - iFixit guide marvellous as usual and replacement trackpad performs perfectly. So good to resurrect

the trusty MB Air!