Getting the Barracuda back on the road

I would get it running good, make sure the brakes and steering are safe.
Elbow grease and soap and water with a few cleaners added will go along way to cleaning the interior.
If you are going to repair the floors at a later date, just pop rivet some tin over the holes, use some ordinary house window caulk to seal the patch down.
Drive it, to many people tear right into them and then loose interest because they are in over their head, keep it running and driving.
Maybe a few small projects at a time and the car will be finished before you know it.