This will be our first time there that week as well. Planning on MK on the 3rd and EP on the 4th. We made ADR's at both parks on both days. According to my research in the past 10 years the MK had a Phase 2 closure on July 4, 2014 and a Phase 3 closure on July 4, 2013. The only Phase 4 closure at the MK was on April 7, 2009 (the same year they also experienced Phase 2 and Phase 3 closures during the same week). We were there that week...it was INSANELY crowded. Like could not MOVE crowded. We were in the back of the park by BTMR and took the train back up to the front because it was impossible to walk and we left MK by like 11:00 am. The signs were already up out front when we left announcing the phased closures. I am hoping it's not THAT busy this year but that's also one reason why we're doing MK on the 3rd. I am hoping the South American tour groups are limited in number too again this year as they were last summer. We plan to arrive at MK by 11:00 on the 3rd for an early lunch ADR at the Plaza then we have dinner at CRT. On the 4th (depending how late we're out on the 3rd) we may do HS in the am then water taxi over to EP around the time the WS opens. We have dinner at Tokyo Dining that night and may to just watch the fireworks from the steps of the Japan pavilion after we finish dinner. I have high hopes that EP will be manageable on the 4th as I was just looking at restaurant availability yesterday and there are still openings to be found at most places (except LeCellier & Via Napoli for the most part).
FWIW:
A Phase 2 Closure means the only guests allowed thru are: Those staying at a Disney resort, AP holders, Those re-entering the park that day, those "hopping" from another park, those with in-park reservations or appts., those arriving via Disney transportation.
A Phase 3 closure means the only guests allowed thru are: Those staying at a Disney Resort, AP holders, those with in-park reservations or appts.
A Phase 4 closure means the park is closed to all arriving guests.