AGOPEN on a Challenger 85a tractor

[Larsvest]

Maybe this can give you a hint.

AgOpenGPS and Swathers

After learning about AgOpenGPS, this summer I wanted to get a gps going in our MacDon Swather. However after reading into this a bit more, I see it makes use of wheel angle sensors. Of course the swather uses a hydrostat, so there wouldn’t be a wheel angle to measure. Does this mean there is no way to get AgOpenGPS to steer our swather? Thanks for any help