Here's the list of mods:
Flamethrower stock is extendable/collapsible
Modified neck so he can look straight ahead
Swapped his lower legs so that his legs are the same length
Added holster to right thigh
Modified elbow area on both arms to enable two handed poses of holding his flamethrower and pistol.
Unfortunately, his helmet and gas mask connection point is still really hard to get to line up 100% but it's only really noticeable in pictures though.
Here's the pics:





Stock extended:

Stock retracted:

Unhelmeted shots:



Drawing pistol:



