Dolphins..
OF230 is obsolete..use DS230.
You had submitted DS230 PART1 with PACKET3 , not PART2.
You need to take DS230PART1 and PART2 with u for the interview.
Do not sign PART2 , that should be done in front of the consular officer.
Tax transcripts look different ( more official ) from the return forms(1040)..but they contain the same info..better take transcripts for the past three years,..,I did that..
I think Employement letter is okay if its 3 months within the interview date.Make sure to get it notarized..
Shanks