I-45 divides Texas into Southeastern and Southwestern. ...at least that's what I've been told by numerous Texans. College Station is as SE as you can get in Texas, other than the University of Houston...which will never become an SEC member. Mizzou sided with the Yankees. F them. 
Well, where I get confused on this Texas A & M thing is that I don't ever recall any Texas A & M fans coming up here in automobiles with any Confederate regalia--the Dixie flag--and so never formed even the vaguest notion they considered themselves southerners.
Texas A & M fans are certainly nothing like fans of Alabama and Clemson. Not even close.
And if one's proud of their Dixie heritage, Nebraska's about the "safest" place to assert it, to show it off, to boast about it. We weren't even around in those days, and here, the American War Between the States is about as remote and far away as the War of Roses 1460-1485. We know it was an important event, but that's about it; there's no emotion attached to it.
So if any Texas A & M fans wished to show off their Dixieness, here was the place to do it. But I never saw such a thing. Again, they struck me as being very much like people from North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, and Texas, not like people from the South.
As for Missouri, I'm confused by an earlier comment of yours, sir, where you said the Big 10 didn't want Missouri because of "academics," which I take to mean Missouri is, uh, somewhat deficient in that department.
That's not the impression we ever got here; the impression Missourians always gave us was their academic and intellectual eliteness, their superiority to us. I never looked into it, but just based on that, I always figured Missouri was a top-notch academic institution.
As for the War Between the States, while Missouri was "officially" part of the north, its sentiments were wholly southern, and I guess more Missourians served in the Confederate forces than in the northern forces.