|Next are the tools, the main ones you'll need is a 1 to 1.5mm pin vise, a 3mm pin vise and optionally a hobby knife.|
Then long nose pliers and optionally a side cutter
the first step is to use the long nose pliers to pry off the previous ball joint. Ideally the joint would come off in one piece but if the bond of the adhesive is too strong...
...The joint breaks off, leaving a large chunk stuck in the hole.
Here is where you might need to clean up the cut joint using a side cutter to trim off the excess plastic and a hobby knife to make sure the surface is flat.
Then next main step is to drill a guide hole in the middle of where the old joint was using the 1mm drillbit and then progressing to the 3mm bit for the main peg hole.
Repeat the process of the previous picture to the forearm, making sure to drill in the MIDDLE of the socket.
All that would be left is the assembly of the arm. Ideally you should drill deep enough to conceal the pegs of the ball-swivel joint.
This would be the result of the mod to the arms. Next time we'll deal with adding the same kind of articulation to the knees.