Sorry, I should have mentioned - I used an alignment tool when putting the pressure plate and clutch disc on. I am a rookie, but not that bad of a rookie

I do have the splines engaged - I'm just less than an inch away from the transmission being flush to the bell housing.
It feels like the input shaft is bumping the side of the pilot, or perhaps the flywheel, so I figure I'm just needing the alignment to get that front part of the input shaft to hit the hole in the pilot.
I will get a helper and fish around some more. Thanks for the words of encouragement!