quick bodydrop question(88-98 chev)

hey just a quick question,my 89 shorty 1500 got t boned so I pulled the cab,and am switching it with a 93 cab,I figured I "might as well" stockfloor it while the cabs off....

question is:how much drop is it to get the rocker and bottom of framerail equal(just to lay rocker)??

thanks guyz n girlz

if the truck lays out properly 2 3/4" - 3" BD will do the trick.