Well...I've had time to cool down now after hearing about your plans to widen your kb10 body!

I'm still of the opinion that the original setup is brilliant, simple and easy to maintain. However, if your dead-set on widening it, then good luck to you. I've never heard of the vanette front suspension swap. What section is wider? Is it then the arms, the cross member or both. The spring must be. Nowing datsun, they probably used many shared components!

The panel work shouldn't add too much I guess. The diff, motor and gearbox will add a quite a bit though. If your doing any sort of hill climb or circuit work then a steel cage will be needed.