Methyltransferase which mediates trimethylation of cytochrome c (CYC1). L-lysyl-[cytochrome c] + S-adenosyl-L-methionine = H(+) + N(6)-methyl-L-lysyl-[cytochrome c] + S-adenosyl-L-homocysteine The SET-like region, although related with the SET domain is not detected by any prediction method. Belongs to the class V-like SAM-binding methyltransferase superfamily.