Sean,
No gears here. But I was experimenting with a little idea of mine, and just happened to use the transmission gears for the experiment.
http://www.harleykmodel.com/database In the "Enter Part Number" box, type in: 35* then click Go. You will get a listing of the transmission gears as they changed through the years.
The idea is to scan all the Parts Books, and convert them (OCR) to plain text - which could imported into a database of parts. Then you could search the database to find what goes on what. The experimental database is actually pretty close to final form, but the only data in it is transmission, and I hand-typed all the data into it.
The problem is the OCR (optical character recognition) process - the OCR programs I've tried do a truly horrible job on the parts books. Not only do they make little mistakes, they make huge mistakes, and so far, are totally unusable. I'll keep investigating, but even after I find a suitable OCR program, it will still be a multi-year project. Or an eternity. But enjoy the gears for now.
Dave