Here is the Clockwork Goblin Miniatures US heavy walker called the Grizzly. Of all the Clockwork Goblin Miniatures I assembled, I found this one the most difficult.
For the main gun, I had to drill out a hole. For the leg & arm attachments I used some green stuff along with glue. By green stuff I mean that modeling puddy or Kneadatite Epoxy Modeling Putty where you mix two colors (Usually yellow and blue, which when combined makes a green color.)
The green stuff makes the parts stick to other parts and then allows the glue to dry. I use this method a lot. I suppose I could have also pinned the arms and legs, but the green stuff is much easier to use.