cedar siding w/ mold/fungus on back side

I’m replacing some rotted cedar siding. Some better pieces have small amt to large amount of black mold.. some pieces have large amt of white fungus growth … ideally I should just replace it w/new , but I was wondering if it’s worth trying to clean off the mold & fungus to hold down the expense of the job? I would then prime all the pcs before painting. Your opinion would be appreciated and comments on any ways to do it ( clorox, or a specific chemical )