Here's another article for v6 modifications:
V6 Mustang Modification Guide
Just some advice based on past experience...I'd stay away from RPM Outlet. They are notorious for messing up orders, taking forever to ship products, etc. I had issues a few years ago, but I highly doubt they got their **** together...I'd stick to site sponsors.
VMP Tuning, Bamachips and Brenspeed are great for custom tuning if that's what you want to do.
12 Black GT500 SVT PP l VMP TVS l JLT123 l O/R X l 28x11.50Rx15 M/T Street R's l BMR Suspension l Recaros
03 Sonic Blue 3.8 / 17 Magnetic Fusion Sport 2.7 EB