For what i could find they tried to get the new body ready for christmas 1977 but the molds could not be done that quickly, and they produced some hybrid figures next year before all the tooling was ready. First they introduced the new head, hands and feet at the beginning of 1978, then later that year they added the new legs, and on january 1979 they got the new torso and arms ready,
The 2nd issue figure was basically the gi joe muscle body figure with action man BP joints instead of rubber jounts and an old style neck. They did not use the action man neck post probably to allow the eyes move when the head was rotated.
1978 marked the fall of sales for geyperman. They did not invest more on the figure and the latest addition to be done, the eyes, were retired because that would add production costs to a figure that did not sell well at the time. That's why the eagle eye geyperman was never produced.
The head itself is an exact replica of the late issue palitoy head, but it was done with a rigid material that did not shrink after production, so the resultant head is a litle bit bigger. But the head sculpt is identical.We see it very different because the painted eyes.