The Firestone RH-5 rims are the ones commonly called "widowmakers", and I don't think they were ever produced in the 17" size. If your rims have a removable side flange with either a separate lock ring, or a split in the ring which allows it to be pried off after the tire is deflated, those rims can be serviced by a qualified professional with little danger. Just be sure the mating parts are clean and free of rust damage.

The 18" rims on my 1959 3800 had a special-shaped one piece outer ring without a split, but there were a couple of relieved areas that allowed the ring to be slipped off the main wheel. Those wheels were pretty suceptible to damage by pry bars or rust deterioration that made it necessary to inspect them very carefully when changing tires. I made several tire repairs and changes without any incidents, but I was always a little spooky about the design.

Does your truck have dual rear wheels? If so, the wheel design will be different than the ones for single rears.
Jerry

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