Imagine, if you will, that your wife's 78 year old uncle offered you his 1970 CB750, that he purchased new in May 1970; then imagine that you did quick research and when you saw the bike for the first time you saw a frame manufacture date of 12/69 and an engine serial number less than 7000! Then imagine that you were ecstatic, and bragging the whole trip home with said bike," I've found the Holy Grail!" Then imagine researching a little further and figuring out that K0 is not the same as "sandcast" and that you overlooked the preceding "1" in the serial number E 1016*** .....
. That is how my day went today. Still a great deal, I will be reading a lot around here. Looks like y'all have assembled some great info.