To fix a set of captain's chairs with a broken armrest, I made this repair plate. The factory plate almost looks intentionally weakened, and they don't usually last more than a decade before breaking. Mine should last more than twice that long, if not forever.
Very few '93s use this style of plate - it's much more common on '94-96 trucks ('97 >8500GVWR). All older armrests are welded steel and don't have a replaceable plate like this.
Adjust the setscrew for a comfortable DOWN position for the armrest, and file/grind the other end to adjust the UP stop.
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The driver's armrest plate is MUCH more complicated...
For new upholstery, check
http://stores.ebay.com/RichmondAutoUpholstery?_trksid=p2047675.l2563Bolt
E9TZ18644A92A or F7UZ1660108DD
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F4TZ1560394AA