Added some detail to the blue boxes

[Russ Bellinis]

Before the merger, the SF would do almost anything for power when they were short. A couple of years before the merger, it may have been right after the SPSF merger was denied, the SF was power short, and took delivery of some new power from EMD or GE painted solid grey with SF reporting marks and numbers just to get the power on the road. Those units received the red & silver warbonnet later if I remember correctly.