The seatback is mostly composed of two stamped sheet metal Shells that are spot welded together.
There are a few critical reinforcements, but the real "weak link" is that the recliner mechanism only stops the outboard side of the seat from moving... this creates
a "Twisting" moment that has the end result that you are in possession of...
a lardass driver (or someone like me, 6'4" 300lb) and any kind of reptetive stress and the seatback fram bends back on the inboard side, and bending it back isn't always possible,
let alone practical.
I'd generally consider it a waste of time to fix the original seat and I'd simply go shopping for a pair of later seats, the seats used 1989-94 are simply nicer seats, particularly if you can track down a set of Explorer sport or Ranger STX seats.
IF you really want to take something apart and do any welding take apart the NEW (unbent)
seat and do your welding to reinforce it.
And there's something else I need to suggest... since you have a 1987 Supercab (Like me!)
there's a great upgrade you can do... you know that double slider seast track you have on the passenger side? How would you like one like it for the drivers side? it makes it a whole bunch easier to get stuff out of the back seat...
But there's a further mod to that track... on the inboard side there's a little steel cable that limits forward travel... remove it and when the track is released the seat will go all the way
to the steering column...
These drivers side "Double slider" tracks can be found in Rangers, Bronco2's and Explorer sports, but be careful sometime in mid 1991 Ford changed the floor and the later ttracks won't fit your floor.
Look around the site there's a list of seats that will more or less bolt directly to ranger tracks
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