Mods, please consider moving this to the Wheels/Tires forum, with the other TPMS threads, as the other members that have been looking into this problem and contributing may be able to help and may have not regularly check the general Legacy forum (thinking of Opie to come up with the part number for the ECU). This topic has come up numerous times, and this seems to be as close to a real solution as I have read about.
The only other solution that was suggested before that I have been considering was a manifold where the TPMS sensors are all mounted and then pressurized through regular air fitting. The rather large air bottle pictured in the other thread may not be needed (so it could be mounted in the spare tire well), and an aspiring inventor/machinist/engineer/vendor could come up with a very useful mod for a small investment in time and materials that would likely find a number of potential customers through this web site. My recession adjusted one and one half cents.