IF you get good quality oil (not cooked to death, minimal meat fat), and you settle it and filter to one micron or better, it will work fine directly in the tank, no conversion needed.

I mix said well filtered decent quality oil with a cup or two of gasoline per 4.6 gallon cube, and only at ambient temperatures above 40 deg. F.

Have logged about 100,000 miles using this method with few problems.

After 30 K one of the vehicles (85 300D) got a little funky, sluggish, clouds of foul smoke. So i did a week long ring soak with Marvel mystery oil as per elsewhere on this forum, and she's flying down the road again.

When you first start running this WVO/gasoline mix, some crud may come off the walls of the tank, resulting in repeatedly clogged primary filter for a few hundred miles. Maybe drain the tank, and after a few hundred more miles, the problem will clear up, and then you are in for thousands of trouble free, inexpensive, and ecologically preferable driving.