can an A-body tow?

Engine performance-wise and from a durability stand point you won't have any issues.

Back when I had the 7-1/4" 2.76 geared rear under my car, and this was like 3-4 years ago I did this, I once had to pull my boss's F-350 Quadcab Dually up a huge hill with my car. It had a seized parking brake, and the hill was maybe like a 6-7% grade. It did fine.

Why? The slant is a torque monster. Great for towing. 200 ft/lbs of torque @ the flyweel at 1200 RPM will make a surprisingly heavy load crawl. Now facing let's say a 4% grade with that truck on a trailer and trying to tackle the hill at 50 MPH? No way, not enough power.

As Rob said, a big issue is gonna be trailer sway.

If I'm not mistaken you live in a flat area, but have you ever took a heavy load on a trailer with no brakes down a big hill with the load being heavier than the tow vehicle? The trailer will push the tow vehicle obviously, and in the tow vehicles resistance to the pushing force, the back end on the vehicle will begin to sway or fishtail. And if you hit the brakes, it gets even worse, not fun.

With a light tow vehicle you key factor is gonna be brake biase.

Ever seen those flat bed tow trailers that U-haul has? They have it setup so that there is a master cylinder mounted on the trailer tongue, the hitch slides on tongue and is attached to the master cylinder pushrod. When you hit the brakes, the sliding part of the tongue/hitch gets forced back torwards the trailer pushing on the master cylinder pushrod and activating to trailer brakes.

Here's the problem. This provide NO controlled brake bias. For the split second it takes the trailer brakes to engage, the tow vehicle is doing all the braking and still yet after the trailer brakes engage the tow vehicle is still doing the majority of the braking. If you have a tow vehicle lighter than your load by a substantial amount, this will be a problem and result in the trailer sway I covered earlier although, granted, not as bad as not having trailer brakes at all.

You're best bet is going to be a trailer with electronic brakes and this will allow you to program your brake controller to handle, let's say 60-70% of the the braking duties. So this way, the trailer will be pulling on the car during braking and will be stopping the car as well as the trailer.

To answer a question, I've never seen a tow dolly with electronic brakes but I don't see why they wouldn't exist. I don't like tow dollies though, they are a PITA compared to a well setup flatbed trailer.