Finally soldered a battery holder into my GC. This is the first time the clock is running in at least 5 years. More pictures below.
I know that this isn't a new mod or anything, but I just took pictures of the process along the way anyway.
After desoldering the old battery, you can put in the battery holder. It's just a slight bit to wide, so you'll have to bend the tabs inwards.
Just solder it in afterwards!
And that's basically it. Put in a new battery and never worry about the systems clock anymore :)
Yeah, it's a great mod for the many consoles/cartridges that are affected. But it seems like there isn't enough space for something like this in GBA cards. Unfortunate, I love the GBA.