The one I mentioned in my post has that and everything you will need. And the tensioner is spring loaded. And the mounting bolts are standard to the block and heads so it will fit any appropriate gen 1 Chevy. And the truck set ups seem to be more compact vs the later car set ups which are spread further apart. Scour the wrecking yards, you'll find it. And if I remember, hot rod to the rescue did a technical article on it and will give you the entire list of parts and years, makes and models. If I have time later, I will look and post it. I think it is archived in my iPad.
