TOPIC: Johnson and Evinrude, whats the difference?

I've heard a lot of stories on this subject, just wanted to hear some more. This question is mainly about the companies in the 1970's. What is the difference in Johnson and Evinrude? Just the hood design and colors? I've heard people say the powerheads are the same and one guy on a forum said he's met guys who worked at OMC (Waukegan, IL) back in the 70's and they said that they're the same. I've got a 79' Evinrude and bought a 76' Johnson hood from a parts motor so I could do a matching hood/boat paint job for my little red runabout. I wanted the boat to have a Johnson hood as my boat still has the nice vintage original Johnson dashplate. The hood fit perfectly, the latches were the only thing a little different. I've always thought of the two motors as basically the same, like Chevy and GMC. So whats the difference in these motors??? (Their connection in the 70's)

Paint and Hoods. Beside that from the early 50s they are the same

You could use the cowl base from the Johnson,then the latches would work?