Letter before ar

The fitting missing letters in OOGLE MA

With 39 Across, Am I making sense or a hint to two pairs of two letters in each starred clue's answer

Don't overlook this news letters

Greek letter that refers to a lone wolf, in Gen Z slang

Go off the like the last letter of 8 Across

*Letters before an addendum

Letter before 35 Across

Letter that comes before upsilon

Letters that come before AA

Proof letters