why don't you buy spacers designed for a TJ? Like Spidertrax?
i'd be very wary of an add for wheel spacers advertised as hub centric, using a picture of non-hub centric generic spacers. Also, they do not describe the alloy of aluminum used, and they are not anodized for corrosion resistance.
also, Explorer's have a smaller diameter hub center bore than TJ's do....which could be a problem.
also, those are 1" spacers. Normally you 1.25" is preferred.... smaller and you may need to trim the front wheel studs. Longer, and you may need to extend the rear wheel studs.
I don't know about you, but for stuff like this that your life depends on, I prefer to buy the quality product that is proven - not some knock off cheapo junk.