and to complete the assembly and make it as solid as it originally is, you may want to reinstall the 4 small pins removed on step 4 (read comments), for which you need delicate tweezers - with the right one, it was much easier to reinstall than I tought it would be.

this is good point and not mentioned on this procedure

Despite my observations on steps above, I did follow this guidance and it ended successfully, thank you for the instructions!

FYI I also got the essential toolkit, which I used to perform this task - very good and useful basic kit, I recommend it.

Final comment: those 20-25 minutes expected is for professionals or those with experience doing this kind of watch maintenance. In my case, first watch I ever opened (though having some experience with bigger electronics), I spent near 3 hours. If, like me, you have never experienced watch maintenance, consider it 3-4 hours to do it as careful as possible.

and again, the blue opening clip is best here to slide under the battery.

Detailed description like this is good to understand what is underneath, stuff we have to handle before actually seeing them - this is the kind of step description I mentioned to be missing before.

I could handle mine without disconnecting those flat cables - it is harder to work with the parts connected to each other and demands special care, but possible, worked fine to me.

I would say this procedure misses some steps, and this particular one is another glued part, but not as strong as the rear cover, so apply some

I do not see any need to remove the o-ring.

I have used a hair drier: 10cm far for about 10 minutes; reheat it for couple minutes during the process, the glue must be soft to avoid breaking the rear cover.

I have the essential toolkit: in addition to the description above, I have used on extra opening pick (total 2) and the suction cup. The glue into the watch is !&&* and I am sure many breaks the rear cover because not ungluing enough of it before pulling the cover off. I found out that the rear cover offers a very small flexibility, but at least some flexibility (it is not absolutely hard as a glass piece as others say).

Action: I have applied the suction cup on the rear cover and used the opening pick on one of the sides *while* applying some preassure to open with the suction cup (after heating it up to soften the glue) - that allowed inserting the opening pick without brutality; then leave the opening pick inside, and do the same procedure on the other side with another opening pick… and keep “digging” in until the rear cover releases. I have re-heated the rear cover twice during the whole process. Rear cover removed without any damage caused by the process.

I wish I could add pictures.