Yeah man 2 to 1 should be fine you really don't need any special number just enough to take some of the harmfulness away from it. I don't remember what we used now but a buddy of mine and I sprayed the living bawls out of my engine and let it sit for about 5mins or so and sprayed it down again and hosed it off real good. On the 4.6 you really gotta make sure you get all of the water out of the fuel injector ports and from under the COP's but since you've got the 5.0 I don't think you should have too many issues. Just let it sit for awhile before you drive it to let any extra water dry up. We used a vacuum cleaner in both suck and blow (laugh it up lol) to get all the water out of mine. Also you can pick up a little 99c tooth brush and use that for the tough stuff. That's what I ended up doing. The Bob Barker edition toothbrush is now a Mustang Cleaner edition lol. Like Rich said tho, don't use it to brush your teeth again

haha
Take before and after pix! You'll be surprised in the difference!!