"How do I make a section 1.266-1 to capitalize carrying charges within turbotax?"
There is no way to make the election from "within turbotax" in any of the online versions of the program.
In the desktop (CD/Download) versions you can generate a blank form (using Forms Mode), type verbiage to effectuate the election directly on the form, and then submit that form along with the rest of your return.
