Try this
  • /cnick -fs1 <NICK> 14

Where f forces a new entry and s1 puts the new entry to the 1st position.
So:-fs1 is forcing a new entry at position 1. mIRC uses the first match, putting it into pos 1 will override any generic colors for ops/modes/etc

To remove it you'd do
  • /cnick -r <NICK>