Because Nebraska is unicameral, there are 99 state legislative bodies in the calculation, not 100. You would need 68 (or 67 if Nebraska is in the calculation) legislative bodies that constitutionists -- not Republicans! -- need to control to get the correctly worded Article V petitions into the Archivist's hands.
Thank you, excellent information. The article here does however mention there are 98 not 99 state chambers. Nebraska and its unicameral legislature bring the total to 99. Perhaps the writer is in error.