'64 Dart questions

To put a push button 904 behind a 360.
Get a non lockup standard ratio trans from a V-8 (preferably a 360), this will be a 998 or 999 trans. Swap everything from the sun gear shell forward into the PB trans. It is not possible to swap the low ratio gears into a PB trans. Then as stated use a after market 360 flexplate with a in balance convertor, or the stock 360 flexplate and stock 360 convertor. While the trans is apart, this would be a good time for a shift kit.