This has been a job on my to do list for ages. I have and old G1 Transformer Galvatron that is in pretty good shape, apart from the battery connector which had partly snapped off. It sounds like a simple job of just taking the figure apart and soldering on a new connector.
But Galvatron has to be one of the most difficult figures to get to pieces. There are so many parts that stop you getting to the screws you need to. First his chest section needs removing, but this is not at all easy, you have to undo a few screws on the sides, then with a lot of jiggling and bending, ping the chrome ring of that is around his neck.
Once you've done that you now have access to the main chest area. You have to remove his hip flaps, then unscrew his groin which allows the upper body to be removed. Your still no there yet, now you need to remove his belt and undo a couple more screws, pop off his crown and you are in!
Blimey. As you can see by the photo you really need to keep track of all the bits as at some point you have to put him all back together.
After all that it was a simple case of soldering on a new battery connector and he was back in working condition. Which for Galvatron is lighting up of the eyes and making an awful sound. So probably not worth all the hassle.