Start the large bird before the smaller ones, and then you can time it so that they get done at the same time. That's what I do in my smoker, but mine is a slow smoker and cooks the meat at 225 degrees, with less danger of the meat drying out - plus we have water at the bottom of the smoker and soaked wood chips.

If you butterfly the birds, they will all cook much more quickly and size will be less of an issue. I have grill pans that I use in the smoker, and they make it easier to take things out, reducing the amount of time that the door is open and the amount of heat loss.

Lars

I probably should have asked here instead of looking all around online! Lars, how would you cook these in your smoker? My friend's is more or less like this model, and he's always used it at lower temps for red meat, probably around the 225 - 250 range.

Here is a link that might be useful: {{!gwi}}

Hello, Lars (and of course, Liz!) Thank you for your input. My plan has been to put the large bird on first (about forty minutes before the two smaller ones). I will some them at about 220/f as you suggest and only check them about every thirty-five minutes. My wife is going to rub the insides with salt, cinnamon, and brown sugar. Since our prior experience has already taught us that the stuffing will not "cook" in the bird, we we going to cook the stuffing on Sat., and then stuff the bird so the stuffing will help absorb the juice of the birds as the cook. Let me know if you don't think this is feasible; as I told Liz, I have tried this twice since last April will good results - but I am trying to improve the product! Thanks for all the help!

Oh, a side firebox smoker. We have that one and have been smoking chickens a half dozen times a year for well over 10. If it has a temp gauge on the lid it is not that reliable unfortunately. Nice to have a stem on wire thermometer.
It smokes much higher temp close to the firebox. I use timber splits and soaked slices of fruitwood so a bit different in method and heat regulating, but the process is the same...avoid opening! But you know that.
Put the larger bird closest to the firebox. Not sure if i would stuff them. Your call. It adds density to the bird and may not cook/smoke evenly. We sometimes 'stuff' in half a lemon, couple apple slices, onion and some herbs. But most often nothing. Not really an issue about safety and un-cooked stuffing, as ours is always a cooked stuffing/dressing also, but not much of a cavity in a chicken. But it just might be soo much smoke flavor. It will slow down the cooking time. Make enough stuffing to have a side casserole baked in the oven?

(i make my stuffing the night before and chill in the fridge as a 'kit'. All the saute veg, sausage, and wet ingredients in a bowl, the cubed toasted bread (dry ingredients) in a ziplock on top as a lid,...toss together with stock just before 'stuffing' to prevent getting soggy...and i do a casserole also)

You mentioned you have smoked chicken before? So you are aware the meat of the bird is often very pink, especially close to the bones. The chicken is cooked, the juices run clear, the temp is correct...but we still have had guests think the meat is raw. Smart to point that out ahead of time.

I successfully smoked a few weeks ago, snowing and windy. The worst conditions. (coulda noodle-whipped the weather man)...rolled and tucked the smoker to the less windy side of the barn and had the firebox into the wind to help with the heat draw. I did spatchock one chicken on a fat bed of wild thyme on foil closest to the firebox. Just to make sure we would have a meal in time. A double stacked sirloin, a whole chicken, 4 pork tips, smashed potato packet and a veg packet at the far end. We ate on time, all went as planned, but tricky.
The spatchock and the sirloin can off well ahead of the rest.

I smoke chicken at a higher temp, 275ish, rather than low and slow like ribs. The pork tips i wrap in a parchment, then foil, packet, with small opening at top. They slow braise for a couple hours, then i open wide and get lots of smoke and still have the juices. At the far end, away from the firebox, the temp is much lower. (especially when it is snowing).

I smoked a turkey a few years ago, along with a traditional one in the oven. Worked out nicely with just fruit, garlic and onion in the cavity loosely. Also at a higher temp. I've read that low and slow smoked birds can dry out close to jerky but i have never had that happen even when i used to smoke them at a lower temp. Just a bit dry.

More useful information! My thanks - I will discuss the stuffing issue with my wife; it may well be that we go ahead and make
the stuffing separate so that the birds cook evenly and I don't have to deal with guessing which one is done and which one is not! I promise to give everyone a report on how this all turns out on Monday (Liz will know on Sunday 'cause she will be here for the meal!).

Save this link for the future. Really good advice for smoking...
I'm anxious to smoke some salmon next spring.

Here is a link that might be useful: hunter angler

For future ideas...
Here is a nice idea for stuffing. A bit of stuffing under the skin on either side of the breast.
I've been reading about duck this morning and wondered about this idea. I'm rotising and have some wild rice and some lamb sausage...I might just tuck some in this way. I'll decide when we truss it. It is dry salt brining now.

Here is a link that might be useful: rotis duck stuffing

Although belated I thought I would thank (everyone) for the help and great suggestions! The chickens turned out quite well, and were moist with a good crisp (but not burned) skin. I have one chicken left in the freezer,and will try some of the suggestions that came in "after" I was done and let you know how they fared! Many thanks to all (again) for the help!