another way to get your duck fat for confit - I butcher one duck, remove breasts with skin intact; then remove the leg quarters together (for the confit), remove wings - set aside all the different sections.
Cut off all the residual fat and skin on the carcass and trim breasts and leg quarters of extra fat. Do whatever with the breasts and use the carcass and wings for your stock.
In a heavy saucepan over low to medium-low heat, render the fat - you do this by putting all the fat and skin scraps into the pan and just let it render. You might want to pour off the 'liquid gold' as it accumulates - two or three times during the rendering.
I have found that the amount of rendered fat from one duck will 'usually' be enough to confit the two leq quarters; but if not, just melt enough lard to make sure the legs are completely submerged in the fat.
You are good to go and you've only had to use one duck. Have fun and once you've made duck (or any kind) confit, you'll kick yourself for wasting so many years!! ;)
an old cook, still learning new tricks!