I have done a window conversion on my car using Aerostar motors. I have helped do two other motor conversions since then on my friends' Panteras using Taurus motors and I have to say that the Taurus conversion is way simpler. There are currently two Taurus motors for sale on ebay for $11.99 each BIN.
Here are the links :
http://cgi.ebay.com/ebaymotors...fPartsQ5fAccessories
http://cgi.ebay.com/ebaymotors...fPartsQ5fAccessories
However way you go, you will thank yourself for doing the conversion. Important to note is that it's very important you remove and replace the mounting spacers(washers) carefully. You will save yourself the headache of trying to lining up the window class/runners on reassembly.
Good luck.
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