dont advice running oil with lucas pumps, if your bosh you can run reasonable high mixs, in summer i was running 100 percent oil straight from tescos but its a bit dearer now, in winter id put 50 litres of oil in and a tenners worth of diesel.

i have run transits vw tdis our merc g wagon runs on straight oil too. and its totally legal not commiting any offence if you mix up less than 2500 litres per year, no tax needed to be paid