71' hud diameter?

[tmc1986]

does anybody with 71'+ disc brakes up front know what the hub diameter is? the reason im asking is because i havent got my rotors for the conversion kit yet but i have a chance to buy a set of 20x8.5 wheels with a 3.075in Center Bore Diameter. the guy doesnt think that they will fit over the hub of my truck but its a killer deal and i need to jump on it now. thanks for any advice. the wheels are American Racing AR104's if you are wondering. oh and its a 1/2 ton truck