If you are mechanically inclined and have done this before (taring apart a dashboard), the 4R is simple. Just remember, firm brief yanks to take some panels apart. Don't force something or you will break clips (been there, done that). Very few here have taken the NAV unit apart. I wouldn't.....Anyway, try these guys (never used them, but where the 1st on google search..... type, "Toyota NAV repair")
Toyota navigation stereo cd dvd changer repair
They should be able to fix the opening problem. Ask them about the staticy reception. Hopefully it's a loose connection.
Oh, congrats on your purchase!! The 4R is an AWESOME truck.
EDIT: Do this only if your warranty doesn't cover it!