my opti is GM part. I bought it from Jason Cromer. I'm thinking that the dowel pin out the end of the camshaft is too long, but I'm not sure. I don't have the stock one shoe, so if you could, measure the stock dowel pin sticking out of the camshaft and let me know how much I need to have sticking out of my comp cam.

I apperciate it.

 

You said it only fits one way, so there is no way besides forcing it the wrong way to mess it up. Is that right?