I would suggest going with the 7.3 PSD, (Only cause of better mileage. The newer ones are getting better but still not as much mileage), then a 4 inch exhaust, gauges, boost annialator, gauge pod, 6637 air intake mod and then the best piece...DP-Tuner. Oh yea...and a good stock of tires! (Side effects may include smile wrinkles, perma grin, less $$ in wallet from replacing tires more frequently and pissed off friends who are jealous cause they don't own a Ford).