If you are going to use a crock pot, don’t add broth. You will make broth that can be used other ways.
Put in a Bay leaf and maybe 12 peppercorns, no salt. Rough chop and onion, a carrot, and a celery stalk. Add your choice of herbs. I always use Basil and Oregano but sometimes add Parsley or Thyme. If you can’t use some of this for dietary reasons, then omit it. No big deal. Put in the chicken pieces and cover it with water. Fill it to the top with water. Then cook it on low for 8 to 12 hours, the older the bird the longer the time.
When this is done, carefully use a slotted spoon to remove the chicken. It will fall off the bone if you are not careful enough. Then strain out the big pieces, I use a sieve. Then take the fat out. You can let it cool and spoon it off the top but I use one of those special cups for defatting. When I can it I strain it through several layers of cheesecloth but if you are using it fresh you really don’t need to. There will be some small bits that get through the sieve but it’s all edible.
I cook the regular chicken pieces other ways but I use the back, neck, wings, feet, gizzard, and heart for broth. I know where the feet have been but if you scald the feet without overcooking them the toenails and sour cover twist out easily and the skin can be peeled. That gets them clean enough for me. It doesn’t take much to overcook them and when you do that skin just tears into tiny pieces. It becomes a paint o get it all off. I normally get about 5 pints of really good broth out of a carcass.
I pick the meat off the wings, neck, and back and use that fro chicken tacos, casseroles, salads, or just to make a sandwich for lunch. You have to be careful or you will get some small bones, but you’d be surprised how much meat you can get off of those pieces if you try.
You can always make broth with the regular chicken pieces but you get a lot more flavor using the bones, cartilage, and general carcass.
I also grew up in a small farm in the 50's. When Mom wanted a chicken for supper she told me and I got one, killed it, plucked it, and gutted it but left the other parts inside the carcass. She took the carcass inside, cut it up, an cooked it immediately without letting it rest. As you said, they were older than the modern babies people are used to eating. Mom did cook them somewhat appropriate for age, like a really old chicken would be chicken and dumplings. She did fry a lot of them and I really liked them. The gizzard, back, and neck were normal pieces of fried chicken. When she fried them she floated them in lard we processed from our hogs we butchered. I mean lots of lard. And she kept the top on the pan to kind of steam them as they cooked. To this day I have no problems with that texture and yes, the older chickens had a lot more flavor than the ones you get from the store today. But using my wife as a guide, many people that grew up on the texture of the broilers between 6 and 8 weeks of age will probably have problems with the texture of older birds fried. They might not like the flavor either.