I have a few of those spoons, but I've never really used just the minnow head.
Are we talking crappie minnow head, or medium sucker head? How would you hook it on there... facing which direction? Will the fish get confused if it looks like it has two heads? lol
Most times it would be a Fathead or Rainbow chub or a small shiner. I just pinch the head off and hook thru the front part of the head. Works great for Walleyes or Perch.