Bruce,
In reply to your question. Refer to the April 2000 issue of Guitar Player magazine where they did an interview with Walter Becker. On page 95 they list the studio gear. As such:
Direct from the article:
with the exception of rhythm parts - which were recorded direct - the tones on Two Against Nature were forged with a variety of amp/cabinet combinations. Bogner, Top Hat, and Bruno heads pushed various 4x12, 2x12, and 1x12 celestion-loaded cabinets, and Becker also used a Mesa/Boogie Maverick combo. For direct tones, Becker played through a Mesa/Boogie Studio preamp and
Boss SE-50 multi-effector routed through high-end Massenburg preamps and compressors.
On Nature, Becker relied on several Sadowsky solidbodies - each sporting two DiMarzio singlecoils and a Sadowsky bridge humbucker.
There is a lot more information in the article, but overall, it sounds like a lot of high end guitars, amps, and gear in general coupled with people who know what sound they are trying to achieve.
I hope that this helps.