First my rant.
The larger tanks are 22 gallons, not 21 or 21.5 or whatever some book says. The large tanks are all 22 gallons. Every Ford I have ever owned has had a 22 gallon tank, and I've put over 22 gallons in every single one. I hate myths.
Now to the OP, you can install an older pre-1995 Explorer 22 gallon tank in your 95+ Sport. It is not simple or easy, but it will fit.
The older 4dr. gas tanks are the exact same length as the newer Sport gas tanks. The older tanks are all plastic, and as such they are molded to fit the space in the truck better. The later tanks are all steel and have lots of wasted space, they take up more room. The older tanks do not have a pressure sensor of some kind that the newer tanks do. The old type of fuel pump sending unit have to be used in the plastic tanks.
I have my old 93 4dr. tank from my 93 Limited, and a 99 Sport tank that I was going to use in my Mountaineer for a TOD BW4406 TC conversion. These tanks are the exact same length. I bought a 99 Sport tank mounting/skid plate, that fits my old 22 gallon tank perfectly. I shall figure out how to swap the newer sensor into the old tank, and use it in my 98 Mountaineer. I already bought a new fuel pickup and installed a Walbro 255lt/hr pump in it.
Give me a chance to work on the plastic tank, and I'll document it in my BW4406 swap. I've got to rebuild my trans first, then I'll yank out the old parts. Regards,
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