The problem deducting that $85,000 for US taxes is that if you fly to Hawaii (which they do almost every week on the AJX contract), you're technically back in the U.S.
A bit of a gray area here. If you come and go on the Gen. Dec. then are you really in the USA for the purposes of this ruling? Just don't use credit cards or leave any other trace of your overnight in Hawaii and it's a non-issue.
That said, both the commuting contract and fact you are being paid by a U.S. Company are problematic. With a commuting contract one possibility is to use the daily per diem rates ( food and lodging ) for your days in Japan. Narita is presently $262/day. Multiple that by roughly 255 days in Japan/working and you still get $66,810 tax deduction. Either that or, as done by the guy in Thailand, spend most of your time off outside of the USA. Then you still qualify for the foreign earned income exclusion based on the 330 days in a foreign country clause.
The best deals come with a resident visa and pay from a foreign company. If it's a commuting contract it is also preferable for the commute to be to an "exteneded layover" in your home base. Again, coming and going on the Gen. Dec.
Typhoonpilot