Hi Vinnie,
Yup, no. 4 is how it should look like, makes one wonder why didn't Dragon do their homework properly, especially considering they do the figures based on the Ron V. artwork which got the cap looking right, and the pictures of originals are there, or even real caps available for purchase.
Pat, the head from Hornet's set has the parade type cap nad the dragons figgie has the field type, but I can't say for sure if the POW's body can't go together with the parade capped head

Greg