Wow....
Anyway. To replace the airbags With springs you remove the air bags and all the stuff for them, grab a pair of rear springs out of a 79-02 crown Vic, grand marquis, or towncar, and put them in. The spring perches are already there
The watts link cars (98+) use the watts link to laterally locate the axle since the control arms are parallel the springs are the same before 2003.
To install a watts link rear you would have to take the rear section of the frame off a 98+ car , but swapping the entire frame is less work. And not worth it unless you want it. A panhard bar is just as effective
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