To be honest, if I had to make a main dish for that many people I'd most likely go with shredded turkey in broth & plan to serve it on rolls with horseradish sauce...or mashed potatoes if someone
else wa going to provide them.
It's something that can be made ahead & even frozen if necessary. My crock doesn't travel well, so I put it in some sort of tub with a tight-fitting lid & then dump it into the crock upon arrival. Because I simmer the bones to make the broth, it gets a bit "jellied" in the refrigerator so it really doesn't slop all over while traveling.
I season the bird differently for this. I slice oranges (or clementines if they're all I have) & slide them under the skin - on the breast from either end & one slice at the top of each leg. Then I pour a bit of OJ or even lemon juice over the outside of the bird. Next I rub Kosher salt & some spices on both the outside & inside. (I never stuff the bird.) (I use a mixture of dried lemon & orange zest, thyme, lemon pepper & ground celery seed.) Put the bird in the roaster, cut a couple oranges in half, squeeze the juice into the cavity & then toss them in & roast it. I have a covered roaster & always cook it covered - until the skin is nice & brown & the meat is falling off the bones. Pull the meat off the bones, chill & shred. (
Everything but the meat goes back into the roaster - including the oranges.) In the meantime, cover the bones with water, bring to a boil & cook all day or overnight in the same roasting pan. Strain out the bones, etc & put in the refrigerator without the meat to begin with...that way you can skim off the fat. Then just combine everything. I can't believe how tasty turkey is this way! (I was never a fan before.) I also have done this with lemons instead of oranges & that's very good as well.