Spring swap question

From : bolo4u

Q: i havent posted here in quite a while but i need some info on a spring swap... my dodge is a 98 quad cab 1500 4x4 with 360 and auto. the best i can tell the right side spring is a 20 and the left is a 21. i have aquired a reunel winch bumper for $250 but its the one built for 2500 series. i plan on doing some strategic lightening of weight on the bumper iutself but am curious if i can should also swap out the front springs from a 2500 series truck and if so which ones would be my best bet. any ideas or info will be greatly appreciated... don .