Join Date: Nov 2013
Location: NYC / TYO / RSW Up in the Air avoiding the Snowflakes
Programs: UA GS 1.8MM, AA 2.1MM, EK, BA, SQ, CX, Marriott LT, Accor P
Posts: 8,058
IIRC security doesn't even open in T1 until ~8am - the terminal itself opens at 6am. It's been a while since I've had an early flight from Narita so it may have changed... I guess the point is OP just take the first NEX - you will have plenty of time - Narita is a very efficient airport.