Everything is hooked up, but the clutch won't disengage with the pedal to the floor, plenty of resistance. Any obvious things to check? thanks!

Is it adjusted correctly?

Same thing happened to me once. It ended up being the pivot tube had split and would flex enough that it would not disengage. It looked fine until you had someone step on the clutch while you were watching the linkage, then the split would show up. Worth a look.

Has the car been parked for a while? Sometimes the disc will rust to the plate or flywheel.If so just buzz it down the street accelerate and let off with your clutch pedal down.
Gus

I had the same issue with my Wrangler this weekend, has been sitting a couple years due to a leg injury that had the Dr saying "NO driving stick"; started it in 2nd (yeah it rolled while starting) out of teh driveway (it had been backed into the garage) by the 1st street corner it broke loose; so far so good.