I'm afraid that a Texas Sheet Cake will have the same problem most of my stuff has. I don't think it will convert well to an 18x24 2-inch high full sheet cake, sturdy enough to be turned out onto a board and decorated with flowers & writing like a bakery cake.
A cake for 70 people is heavy. I need something that has enough structure to manage flipping over on a rack & board.
But thanks (or maybe not

) for the suggestion. I haven't had a Texas Sheet Cake in years. Now that it's in my head, I think I have to put it on my short list of things to make in the near future.