A honest man is hard to find!
WFO comes from way back in the early days of auto racing and refers to a driver who's car is " wick full open". A more modern example would be "pedal to the medal"!
They were comparing it to the oil lamps used for lighting- if you cranked the wick as high as she'd go ( and as bright as it could get ) in reference to your car, then you were pushing it as fast as it could go!
These days most folks would assume you were saying the throttle is "wide effing open".
BTW, I know dropping the back seat will increase the exhaust sound, but it is nothing compared to added sound of the tube. I kid you not- the change is significant and sounds good too.
Drop me a PM if you want to try it. If you cover shipping, I'll let you have it for free. Make sure you've got an opening in the firewall and it will be a 5 minute job.