Need help on backspacing for 01 silverado

im about to order some 20x8.5 and 20x10 billet wheels. What offset will i need to get them in. im sure 5.25 is good enough for the 8.5's, just not sure on the 10's

thanks Jared~

You need 6" on the 20x8.5s and 7.25" on the 20x10s!!

thanks man