Well, I'll certainly support you on the fact of Scots being in Mississippi. However, you have no idea what you are talking about with the whole "Mac" and "Mc" nonsense. In fact, there is no difference between M' Mc and Mac and there is also no difference in those people who dropped the Mac altogether. In all its variations it means "son of" and none of the peoples of Scotland or Ireland used one form to the exclusion of the other. For instance, my surname is McLaurin, we are of clan MacLaren both spellings are a rendering of the Gaelic Labhrainn. the question for the Scots of the 16th century was how to render a Gaelic name in English so that it sounded the same. In the case of our clan those that lived in Perthshire decided that MacLaren did that best, those that lived on the west coast of Scotland and in the islands used either MacLaurin or McLaurin. Plenty of our clan dropped the Mac altogether and became Law, Lawrence, Lowe, Low, Lowy, Lowry etc. so that all of the names of that ilk are sept names of clan MacLaren.
Back to the relationship of our clan/family to Mississippi. My ancestors moved to Mississippi in 1819 and are found on the US Census of 1820 in Wayne county MS. We are further list on the rolls as Pioneers of the State of Mississippi. My immigrant grandfather from Appin, Scotland and his family eventually settled in Simpson County, MS, where the McLaurins stayed for over 150 years. Our migration from the Carolinas to MS was not a matter of one or two families or individuals, instead a great number of McLaurins moved from the Pee Dee river valley near Laurinburg, NC to the area around Simpson, Copiah and Rankin counties in MS. The family story is that a cousin obtained a large parcel of land in MS when it was taken from the Choctaw Indians and offered free land for kinsmen that would come and settle it.
Eventually, McLaurins became Governors, US Senators, State politicians, Judges, educators and ministers in the state. They were no alone. Most of the areas where you will find McLaurins, you find other Scots. My grandfathers did not marry those of non-Scots extraction until very recently. Calhouns, McInnis, Wilson and Sheppards all lived in the area and intermarried with the McLaurins.