caster... negative or positive ??

[Loosej@domain.elided]

Alfisti,
  A '74 GTV has been described by other GTV drivers as having "vague" 
steering.  On the highway, at 65 MPH, the car feels like it is being blown 
about the highway even when there is no wind.
  Should this failure to track properly be corrected by 2 degrees of negative 
caster or 2 degrees of positive caster.
Thanks,
joel lewis
Houston
'74 GTV
'89 milano

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