Originally Posted by
Funktopus
Amazing, thank you. Here's a photo of the piece I can remove:

The circled bolt and washer are the what came with the vitus.. The other bolt came from a Reynolds frame I bought for spares. The reynolds bolt actually holds the clamp firmer than the Vitus bolt, but not firm enough.
The key is on the female side, and can clear the frame. It's a mystery as to why the female side can't get free.
So it sounds like my best move is to get some washers, as I'm thinking finding a bolt with a shorter unthreaded shoulder is going to be challenging.
It could be that the key on the bolt is now slightly tweaked into the collar, because of the overtightening of the bolts...try using a flat punch to gently tap it out while twisting the allen wrench..
Do not try to pry it out...it looks like you have already been wrenching pretty hard on it so be careful not to crack the collar.
BTW the collar on the other bolt looks a tad shorter on my monitor, if that's the case that's why it "almost" tightens the post.
GL, Ben