An auto car on a tow dolly?

just cover the basics...... good tires and good brakes. use lower gears down longer, steep hills. Don't park where you have to back up. And, as I suggested earlier, I'd tow it backwards and forget unhooking the driveshaft/loosing tranny fluids or checking the rear end grease.
In the end, every time I travel the interstates, cars being towed daily.
The only problem with backwards-mounting it on the dolly is that 60% of the weight should be at the front of any trailer (or ahead of the trailer axle), for safer hauling and less-likelihood of trailer sway. I appreciate the suggestion, but I think playing it safe means mounting it front first and disconnecting the driveshaft (I'll bring wire and straps to tie it to the frame).

Very true. Lol, maybe rent a uhaul truck and trailer combo. Then you are covered for sure. I can tell you from experience hauling through that pass even with my 1 ton diesel truck and a car loaded on my trailer it is an adventure to say the least. My dad and brother in law both had Dakota trucks. One was 2wd the other 4wd and I don't know I would trust either to handle the weight of an older real steel car with even a lighter dolly to handle that. It would be bad times to be overheated or blown engine or trans in the pass where cell phone reception is non existent. Especially since it can be 100 miles between even gas stations let alone towns. Unless of course you like to be adventurous. Haha, I usually reserve those types of fun for when I'm close enough for AAA to come get me.
The difference though is that a trailer weighs much more than a dolly, so opting for a dolly will keep my Dakota happier. Not like I'm hauling an RV, but I won't be winning any races since with OD disengaged the engine starts revving up over 55mph. Like mentioned above, the engine and trans are shared from a Ram of the same year, so I got a good powerplant and powertrain already. The frame and brakes were my only concern. The owner's manual (yes I have the original paper manual) states the V8 Dakota can handle 8000-8800lbs gross combined weight (the truck comes in under 4000lbs so with a 72 Demon on a tow dolly I'm in business). I just changed out the front brakes within the last year and they're all around solid (and I'll just keep in low underdrive to help control my speed going down). And again I'd be making the biggest climb with an empty trailer so if I take the return trip slow I'm good. I at least punched in the numbers on uhaul's site and they can allow this combo (with this long of a trip I'd get charged for a 2 day rental, lol any chance I could borrow your dolly for a bit cheaper Pentastar?).

LOL my friend actually suggested I get a AAA membership. My logic: what good will AAA do if I break down outside of cell range where I can call them?

I put together a "just in case" kit:
If I really wanted to play it safe then I'd take the long way around on I-84 since it drops back down into Boise. Only problem is, until further notice eastbound I-84 is closed due to the fire on the Gorge.