Given the numbers that they used, I'm pretty sure that this is a tek for large (~1kg ACRB) extractions. If you are doing a personal extraction with a smaller amount (50g-200g ACRB), I would suggest scaling back the quantities they listed.
Please make an effort to understand the theory of extraction. When DMT is in an acidic solution, it forms a salt and is therefore polar and soluble in water. When DMT is in a basic solution, it is in freebase form and is therefore nonpolar and NOT soluble in water. This is why you use naphtha to soak up the freebase DMT molecules near the end.