Got the motor in today.  Traction motor from an old Clark 25 Forklift.  Thing is a beast.  185+ lbs, 11" dia., and 17 1/2" long roughly.  Has a splined shaft that is going to be a pain to deal with, and looks like it will be very close to not fitting in the car.  But other than that, looks good.  Did a little test run, and it fired up with 12 volts.  Little vibration, and a lot of dirt but otherwise ran smooth.  To be continued...

A pretty good video about the basics of a DC series wound motor.