Stuck mating small block back up to A833. Suggestions?

Thanks to all for the help. It turns out that the hydraulic throwout bearing was not fully retracted.

As a life long ADHD sufferer (and generally successful manager thereof), it’s pretty typical for me to overlook such an obvious checklist item. All of the information you guys provided helped me work through this. I appreciate the help!

And yeah. This is why I don’t maintain aircraft! :)