I'm doing an (extended) 1120-S on a very small S-Corp, shareholder / owners.    Instead of doing payroll to pay  themselves, they mistakenly wrote owners draw checks, no withholding, no quarterly filings.  

I should recharacterize much of this as reasonable salary when I file 1120-S.   What is the best (lowest penalty) way to do this now, so far after the 941 deadlines?