I just replaced all 8 plugs in my 4x4 I did not use the ford styl plug I used the correspondin numbers in Champion
is this a mistake or will it be ok I have been told both
should I have used the platinum?

Its always best to use the oem style and type of plug, no matter what kind of vehicle it is. If it came with platinum, i would stay with platinum. It may run ok on what you have in it, but a small decrease in fuel milage which may be hard to detect, would soon pay for the difference in the platinum plugs. But thats one of those things you could ask a dozen people and get a dozen different answers, and thats just my opinion. 30 years ago, i would say it didnt make alot of difference, but on todays vehicles it seems to make a big difference. If youre not having any performance or drivability problems though, id leave em in there unless you notice a drastic change in fuel economy.