I tried messaging Top Gun about this but they never answered.. I know this is an 8" lift kit.. But what do you think for tire size? I was guessing a 38 with an 18" wheel?

I have an 2005 regular cab long bed, and I really like this look, but I want to keep my current 20" wheels..

 

Here is the look I would like, dont laugh at my MS Paint skill haha!!

 

Here is mine with 40s on a 9" lift if you want to use it as comparison.
On that topgun truck it looks to be about a 37-38" tire.