Make Barrel Cooker a 8-10 Hour Low & Slow Smoker

This easy method works for any big barrel smoker.
You need firebricks, a rectangular baking pan , standard baking pan is 26X 18 X 1 in.
May need a few bolts & washers to make support.
Arrange bricks on charcoal grate to make a fuse burn, put foiled pan between grates & fire & light one end.
My tailgating grill will burn 6-8 hrs on a load & mt 18X 18 grill will go 8-9 hours. Easy to controll temps seems to want to run 250F
Pics of tailgating cooker & a couple pics of bigger.
I'm sure you could get 10+ hours on a CG soper pro.

That's a pretty slick set-up, so you set the baking pan over the coals for a difusser correct. I like it.

That's some seriously indirect grilling! Does much smoke flavor get to the meat?

I bury wood chunks in the charcoal, plenty smoked flavor.
The pan serves as a heat shield similar to a stone in a kamodo cooker.
This works much better than a side fire box for an inexpensive Horizonal cooker.

How well do you think that would work in a chargriller and would you start your fire on the same end as the exhaust but on the front side?

I think it'll work great om a Chargriller Super-pro.
Get a standard baking pan 18 X 26, With the super pro grate area of 19 X 30 X 1 in, it'll leave a good edge for airflow.
May have to put in a few support screws to support pan.
The fire will work fine either direction.