4/6 Drop wheel help

[mater86]

I have a standard cab stepside truck I'm going to lower 4/6.
I'm looking through wheels
Front 20x8
Rear 20x10 or 20x12

I'm needing help with what offset to get and tire sizes
Any pics would be helpful too.

 

[mater86]

this is what I found
https://www.summitracing.com/cart/estimateshipping#Estimator

 

[mater86]

https://www.summitracing.com/parts/mbw-23215

Okay after talking to some buddies decided on going with 20x8s all the way around with +7mm offset