A pie maker I am not, and experimenting yielded a taste that wasn't as good as it could have been, but all in all it was a worthy experiment. Started with around a 8# pork butt. Coated it with Weber Beer Can Chicken seasoning and let it sit overnight. Did my first overnight cook on a night that was hitting 33-35 for the lows which was perfect. Got the pork on at 7:00pm, plate setter legs up, drip pan with foil under the corners raising it off plate setter, fatcap down over drip pan. 250 starting temp, 5:30am Egg was 200. Brought it slowly up from there and finished the pork at 2:30pm with a BGE temp around 225-235, 19 1/2 hours from starting point. Wrapped pork in foil and let it rest an hour, filtered fat and put in fridge. Stirred up remaining charcoal and put a pie tin where the drip pan had been, and had 4oz baby carrots cut in thirds, 1 medium potato in 1 inch chunks, and 1/2 a large onion in 1 inch chunks in it. Cooked them until the carrots started to soften and shrivel a bit, all around 235 as the ash was restricting airflow. Put the cooked veggies in a bowl in the fridge, pulled the pork and put it in a large bowl in the fridge, and called it a day.Next day I measured out how much pork would fit with the veggies, and it turned out to be 8oz. I used the pork fat (3/4 cup) and 1/4 cup butter and made a pie crust. (Note: should have partially frozen the pork fat to harden it up more) I mixed the pork and veggies, then made a country gravy. (This is where the experiment went awry. I wanted a pork version of steak and ale so replaced 1 1/2 cups of water with a dark beer. It made it all quite bitter, and I would suggest sticking with just country gravy). I did the Pioneer Brand Sausage flavored country gravy packet which makes 2 cups which was the perfect amount for the pie. Rolled out pie crust, got it in pyrex pie plate, mixed gravy-veggies-pork together with some smoked sea salt and dumped it in the pie crust. Rolled out second pie crust, got it on there, sealed edges, and then baked it around 375 for about an hour. We had intermittent wind gusts so holding a steady temp was not as easy as it normally would have been and I was running it lower more often than not as I didn't want it to burn. An egg wash would have been good to help brown the crust as mine didn't brown enough.
In the end I got a pork pot pie with a crust that tasted strongly of pork from the pork fat used to make it, but the bitterness had receded a bit (the beer I had with it may have also helped mask the taste).
I am sure a better pastry cook could have done a better job with the crust, and I know now not to use beer in the gravy, but I definitely had fun spending two days cooking the ingredients on the BGE to make a pie that was then cooked on the BGE. : )