Using CIS as salaried or non salaried

Hi there just a quick question. I get paid via the construction industry scheme so would like to use this to meet the salary requirement. I receive different paycheck amounts every month because I am on price work. Now the guidance says someone applying under cis can as an alternative to self employment count cis as salaried income. Am I right in applying under category a salaried income or should I still go non salaried. My worry is that the guidance only says I can apply as salaried however my pay fluctuates meaning technically it should be non salaried? Any information will be greatly appreciated as applying Sunday :)