on a 90 series I'd always go for a D4D VX auto, I really liked mine for what it was, and even more when I fitted cruise control ( which you can't fit to the 1KZ ones). It was powerful, especially when I found it had a Tunit box but quite vocal, like a tuned up Massey Ferguson, no comparison to the 120 though. on a Collie watch for corrosion behind the plastic front wing arches and the bonnets seem to have a particular spot on the leading edge where they all go. Rear half of the chassis and back axle turrets are very prone to rust.