Wow, good for you! I remember that being really tight in my '65 Barracuda. I've run a Lakewood blowproof bellhousing for a long time and, in my case, that center link needs to come out. If you can, I would reinstall engine and trans together. It is much easier to mount the trans to bellhousing/clutch assembly before install. As in... get it in there without knocking the throwout bearing off the fork. Make sure to use a clutch alignment tool to get the clutch disc centered when installing pressure plate or that trans ain't going in. :)
You probably know all this and you are not even there yet. Yet I yap. :) Good luck!!