Well it sounds like the cooler is the choice for the day Jack.
Still the first step is to do is the exhaust. It sounds like the guysyou have lined up to do it have done the job before plenty of times.
I just find it hard to beleive that just a cooler will give that sort of an increase as displayed in the graph without carrying out other mods
Be sure to post some pics and tell us what she goes like after the job.
Cheers Kev.