Best diesels for biodiesel conversion

The favorite for biodiesel conversions

According to MarketWatch, the Mercedes-Benz 300 Series from the 1980's is the most favored diesel vehicle for biodiesel conversions because of its reliability.

Other suggestions included the VW Passat TDI from 1996 or 1997, or an 8 - 10 year old VW Jetta TDI.