I never knew a Texan to claim the sun rises brighter, bigger, and earlier than on the East coast, but evidently . . . Bulldog has it. If the change is substantive, just add a post beginning with something like, "In post # X above, I said . . . . Then continue [but I meant to say . . .] [I want to add ...] or some such.
For a trivial error or typo--like mipselling--you can leave it. As readers, we rarely notice,or we are forgiving because we realize that self-editing and poofreading is still error prone. Or send me a PM with the crection and I will make it for you.
Same for a minor error of fact, like writing six-weight when you meant 5-weight. That might be important or helpful to change.
Spelling Berkely Berkly Berkley correctly, I can't do it.