[86sleeper]

first of all, the majority of ford techs don't know a whole lot.
i would see how it goes once you install the parts. I bet it will hold for a little while atleast. by zipping through town, i hope you don't mean trying to manually shift your auto. That is not good no matter how much power you have.
also, you don't want to go over 400rwhp generally speaking.
I also would never accept a mail order chip and assume it's right, they did tell you to put it on a dyno before you put your foot in it, right?
why did you choose the vortech aftercooler?
what other supporting mods are going along with your tuner kit?
injectors?, pump?, spark?, MAF?, IAT?