If it's 6%, and plant direct is 3%, then that's over $50 per head at the current market or about $3.60 per cwt.
Add to that additional fees you have selling at the salebarn that you don't have selling direct.
I always figured I need at least a $5/cwt premium on fats at the salebarn to breakeven.
Of course, depending on where you go you might be able to save some of that on trucking.