This is the sort of thought that could benefit many with auto transmissions. Heaven knows they need it. Kudos for bringing attention to the possibilities.
ECT Analyzer referred to is probably only supplied to Toyota. Toyota parts and service may be able to provide a contact.
I do know there are lockup switches available for some transmissions. May turn out to be as simple as splicing a switch into the lockup solenoid wiring. Found this site when looking around. May be of some help or ideas.
http://www.eng-tips.com/viewthread.cfm?qid=59308&page=7
Dig into this well before giving up. You could render a much needed service to others. Let us know what you come up with.
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