The 2.5 inch sigma six figure arms

I have a question about them, well about the Heavy Duty actually. I just got one from a yard sale and found its perfectly sized for a 3.3/4 fig and I have a custom were I think it would be absolutly perfect on. But I dont want to bust open the figure it the shoulder peg isnt anything like the ones on the 3.3/4 figures. I like the figure, its a nice one.

My question is, has anyone opened up these smaller sigma six figures and will they work in the 3.3/4 joe shoulders?

Thanks,
Aegis

I had the same idea actually. Just heat the torso (It's a solid piece so you can't "crack" it open) and pull the arms straight out.

The peg is NOTHING like a 3 3/4" Joe and would require quite a bit of work.