Why not check the vendor you bought the engine from? That's where I'd start. By the way, nice looking bike. Congratulations and welcome to the forum.
Just a word of advice: I'd secure the chain tensioner bracket to the chain stay in a way that will prevent it from loosening and rotating into your rear spokes.
Tom
Great looking bike. I have the same and am having some trouble with it. How did you mount the rear sprocket? Mine is like this (from the hub out): metal plates, rubber spacer, spokes, rubber spacer, sprocket with dished side in. I tried it this way to get the proper alignment, but the outer rubber spacer won't allow the sprocket to go around the hub. Any pointers?