Thanks for your replies, I'm pretty keen to go the two tank system; what with diesel around $1.75 a litre!
As far as switching between the two systems, how to prevent the small amount of cross contamination when you switch from diesel to SVO and visa versa?
**Oops my bad, I just found the subject already covered**
http://www.biofuelsforum.com/svo_use...rtup_tank.html