The FSW program is closed for the year (as of May 8) unless you have a job offer. There is no guarantee that plumbers will be on the list when it reopens. I'd be applying for PR, not IEC. There is a chance you will be rejected (for either) up front based on criminal ineligiblity due to your past convictions (drinking charges, including public drunkenness and DUI, are frowned upon). It's not the end of the road, you can apply to be considered criminally rehabilitated, however, this takes time (up to a year).