Steve,
My understanding is that Ford wanted a colour that stood out more for colour TV than what they ran in 69. The rational behind school bus yellow was that it was cheap and stood out! I believe this was Bud Moore's decision.
Look forward to the upcoming article. Those Mopars often qualified well but had more reliability issues than Ford, GM or AMC.
When u say the fords kept blowing engines. Do u know specifically what was letting go? I know the rocker gear was a weak point even in 69/70.