Catalyzes the methyl transfer from S-adenosyl-methionine to the C-24 of lanosterol to form eburicol. lanosterol + S-adenosyl-L-methionine = eburicol + H(+) + S-adenosyl-L-homocysteine Steroid metabolism; ergosterol biosynthesis. In Neurospora, the biosynthesis pathway of the sterol precursors leading to the prevalent sterol ergosterol differs from yeast. The ringsystem of lanosterol in S.cerevisiae is firstly demethylised in three enzymatic steps leading to the intermediate zymosterol and secondly a methyl group is added to zymosterol by the sterol 24-C-methyltransferase to form fecosterol. In Neurospora, lanosterol is firstly transmethylated by the sterol 24-C-methyltransferase leading to the intermediate eburicol and secondly demethylated in three steps to form fecosterol. Belongs to the class I-like SAM-binding methyltransferase superfamily. Erg6/SMT family.