leveling kit won't fit on a denali?

[Yamahauler1]

I was going to purchase the GM 1" leveling kit (part no. 84608728) but the parts guy says it won't work because my truck is a denali with 20" wheels.
Is this correct?

Thanks

 

[G-50015]

you need to put your year and model in your posts.

 

[G-872477]

you need to put your year and model in your posts.

2012 Crew cab denali with short box 4 wheel drive.