Title says it all, thanks in advance for anyone who takes part in helping me through this

You can... via the console.
To remove a perk, first search for its ID in the console, ex: help "Fighting Stance" 0 - the code is 00052d50. Now remove that perk simply by typing player.removeperk 00052d50.
Adding a new perk is also simple: player.addperk [perkID]. Perks added that way will not use perk points.