Get a hole saw and do the upgrade, save the pieces you cut out, get a piece of cold rolled 1/2 rod, drill, weld, and it is done. I really don't think it would be that hard to do. Never checked the temp, but I can grill a steak, you are cooking over a fire, a nice option to have
Mine runs about 20 to 30 degree cooler than the actual chamber so ive had m chamber to 400 so I woul think the warmer easyily to 350...I always cook my beans in mine and they cook fine but when low and slow in main chambe it is what the name implies a warmer and will only be around 200 or so...Hope that helps..Mine is the newer one
Kurtsara-with the deluxe setup on my 60- if I have all three vents closed and the damper plate on the 2 bottom vents, my warmer will hold at 140°-150°. If I open the vent between the food chamber and the warmer box my temps will go up another 50°-60°. With the damper removed and all the vents opened up I can hit 350° in the warmer box while the smoker chamber is purring along at 230°-250°. By adjusting the three vents I can get the warmer box to hit the same temp as the smoke chamber.