Cross-Country Road Trip in a '68 Barracuda

Well, I have an unfortunate update on the road trip. We tried to make it to Denver last night, and as soon as we got over Grand Mesa the rear axle started making too much noise for my liking. It had been getting slowly louder throughout the trip but last night it got bad. A low rumbling/growling that gets higher in pitch with vehicle speed and goes away when I turn left or right, plus a driver's side backing plate that is dripping gear oil makes me believe the axle bearings are shot. It may be fine but I'm not driving a rear end that could potentially lock on me going down a 7% grade at 60 MPH. I'm still working on a plan but it sounds like for now I am going to have to leave the car at my grandparent's in Eckert, fly back to Indy, and then fly back to retrieve it either with an axle bearing kit and radiator, or just have it shipped.