Ok, here's some pics of what I've done so far. (BTW, thanks to Deadpool and the others who suggested the ball joint on the neck thing, I didn't even think about that.)
Thigh. I cut off the top and bottom parts and attached them to the legs of another robot which had the joints I wanted.

Arms. I cut off the joint where the arm connects to the shoulders and placed a sheet of styrene on the part where I just cut so as to strengthen it. I'll drill holes on both the joint and the arm so I can reconnect them with screws later on.


Head. Due to Hotrod's high collar, I had to cut the entire neck off as well as some of the collar itself. I then attached a ball joint and a polycap socket on the collar and neck with some putty.


As a bonus, I decided to modify Hotrod's Targetmaster buddy as well. I cut off his arms, drilled holes on them and will reattach them with screws later on.

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