Manual transmission vs Automatic Transmission: what tranny is good for truck pull Tug of war?

I found a 1997 Ford F-350 crew cab long bed Powerstroke Diesel. It has a 5-speed manual and I was going to do truck pulls (truck Tug of war) at a mud bogging show. What is a good transmission for Truck tug of war manual vs automatic?

An automatic would be better…

The main issue is not auto trans against manual trans it will be the mechanical condition of these trucks and there engines. And also what state the mechanical clutch is in when compared to a torque converter this fluid device has no elements to slip against each other like a mechanical clutch does.

If you buy that truck put a triple disc South Bend Clutch or equivalent in it will be better than any automatic!

Manual with low range and 3 diff locks.

Automatic with a massive fan assisted cooler. I mean large radiator size in the back with big electric fans to keep the transmission oil cool.
You probably want to increase the size of the transmission pump.

Manual the clutch is liable to burn out.
Also with a manual you have the initial problem of getting moving.
Expect things to go bang.
Take the truck on a trailer and expect to be taking it home broken whichever way you go.