I'm going to tell you a little trick, but be careful when you do this as I don't want anyone melting their coil.
The reason we send the extra little shim washers is because the stock washers on your lower Explorer shaft are usually in varying degrees of wear. If they are worn too much then you need to use a shim washer. The ideal situation is not to have to use any additional washers at all.
To start with you should always have NEW stock washers on your lower rod prior to installing the WOT coil.
What happens is over time these washers wear down, as they wear down, your coil becomes loose and you tighten the nut and bolt. The ears on your coil tug in and snug up nicely because you really are not making too much of an adjustment; just enough to compensate for the wear. You use it until it starts to flop around again because of washer wear, and you snug it up some more.
Because you do this over time, a little at a time, you really don't pay any attention to how much those coil ears have moved in. Sometimes as much as 1/8th of an inch!
Now you get a new coil, and it doesn't seem to fit. That's because you have worn the washers down to almost nothing. So first, make sure you start with NEW STOCK Washers, the ones with the little tabs.
Now go ahead and put the WOT coil on. If it still seems a bit loose do the following.
Take the lower rod off of the coil and reinsert the nut and bolt in the ears of the coil. Get your wife's hair blower and put the heat on and slowly heat the ears. This is thermo-molded plastic and it is very easy to warm up and reform. Tighten the nut and bolt a bit and continue to warm the ears. Keep tightening and warming, until the ears are nice and parallel, or even toed in a bit.
Now either allow the coil to sit and cool, or turn the hair blower on air only and cool the coil ears down. Do not remove the nut and bolt until the coil has completely cooled.
Once you have completed this exercise you will see that the lower rod will be nice and snug with no extra washers needed.
Hope this helps.
DOC