I have played with sway bars,I am running 27mm on the front (stdwas25mm) I had a 19mm after market sway bar on the rear(bolt on) ,
The reason I changed sway bars was to make my 96 series 2 double cab handle, I have since removed the rear sway bar as it was a total waste of time an money,on corners at speed I can get oversteer which I am trying to get rid of.
To get rid of oversteer which all these trucks suffer from you need big front sway bars,an no rear sway bar.
You can find that info anywhere on the net.