Quick Fuel ss-680cfm Vs

I bought a quick fuel super street series 680cfm vaccum secondary black diamond edition carburetor. And my buddy brought me his 74 half ton short bed 4x4 chevy truck that has a fairly warmed over 355 in it. He had an old holley on it that was leaking fuel everywhere and running like crap and it needed a lot of attention.
I talked him into buying a super street series quick fuel, He wanted one and told me that if I bought it he would pay me back with an insurance check that he would be getting soon. Well he never got the insurance check. His house burned down and he was getting huge insurance checks, so I was not worried about him being able to pay me back, because a month prior I watched him deposit a 15 thousand dollar check into his bank account. Well there was an issue with what he was claiming to have lost and the insurance company did not cut him the check that he was going to pay me back for. And I told him sorry dude, but the holidays are right around the corner and I am going to sell this carburetor. And he said ya i am sorry that worked out the way it did. And i never set the carburetor up to run on his 355, I just bolted it on and fired it up and set the floats and the idle mixture screws with the vaccum gauge. This carburetor has literally only been ran one time for about 20 minutes.
So i already have one, and i don't need another one. So here i am selling it so i can put some gifts under the Christmas tree for the kids.