An eBay listing for this kit mentions that it works for the GT and v6, however, on Zex's website, it doesn't mention anything about the v6, except for a chart with small font where it does say v6 in parentheses. I would think that if it worked on a v6 they would make it more apparent so they could sell more nitrous kits. Any reason why it wouldn't work on a 4 liter? Also, what other mods would be necessary? Zex does recommend a colder plug, but would this degrade performance @ everything other than WOT which is when the juice automatically kicks in?

It will work on the V6 4.0. Just remember the tps is on the driver side when you install. 75 shot is safe with some removal of timing, 100 shot is fine with a good dyno tune.