I tried this and works for me but I know some will think its a hideous idea.
I knock myself out on the flight.
Once a/c is airborne I take two of hi strength halsien (sp) sleeping pills. In your case do it on last long sector into destination. I sleep like a SOB into that port and wake feelinf refreshed and ready to go. Have done this several times now and cant believe difference it has made.
Told several of my friends and they do it LAX - AKL and cant believe how refreshed and better they feel.
Wont work for everyone, and to be honest is an issue if you are diverted or there is an incident and you are drugged to the eyeballs.