I've used such an approach with mag mount whips and/or quarter wave whips attached
to the roof rack rail on my car. They aren't perfect, of course, but the are quite convenient
for a FORWARD/AFT indication. In a town with streets neatly laid out on a square grid you
simply drive straight as long as the display reads FORWARD, then make a right turn when
the needle centers. If it reads AFT turn around. This can quickly get you close to the
transmitter, as long as you don't get confused by reflections, etc.
Sometimes it is helpful to also have LEFT/RIGHT indication - you can do this with the same
receiver and just switch in a second part of antennas.
I find the TDOA still works better as a rotatable unit, however, as that allows you to
spin it around and count the number of times that the needle crosses the center. If this
happens more than twice in 360 degrees you are in an unreliable site and shouldn't trust
bearings. For hunting where the street layout is less tidy, I'd consider instead putting
a pair of dipoles on a rotatable mast instead of mounting them to the roof.