1994 E150 Conversion Van

I have just acquired this vehicle which is in excellent shape but is not firm on the road. It has the old type suspension. Does anybody have experience in installing equipment to cut down on the body lean & sway? I see lots of shocks advertised that say they will do the job, but which works best? I have read where a rear sway bar will help but if too heavy will make ride more harsh. Any suggestions will be appreciated.