Next the radius and ulna (forearm bones).
This is more tricky as I need a small socket at the elbow, and a larger socket at the wrist.
Cue the parts... a TT upper body, a pair of HT gloved hands, and the radius and ulna parts of the model kit.
Cut off the TT wrists at a height just long enough for the lugs of the wrist ball joints to fit into. Trim the forearms and drill shallow holes for the bones to fit into. Glue and miliput as usual.
Then the elbows. cut the gloves up so that all that is left is the socket and a bit of rubber around it. Drill two holes to fit the radius and ulna in their correct position for an elbow, then a generous layer of miliput. It is better to have a big blobby elbow, then sand and shape as much as possible without losing stability.
Once dried it is time for a fitting.
Dizzy