I have a very old Presto canner book that is from my mother and was printed in the 1940's. I still use the book and the recipes and the canning instructions.
I am presuming you are going to kill and pluck and clean your own chickens and you already know how to do that.
Here's how they say to process a chicken (I use some of my wording for clarity)
Young chickens should be packed raw to retain better shape. To can raw, pack serving pieces firmly in clean quart jars with little or no
space between the pieces. Add 1 teaspoon of salt to each quart jar. Place the jars (no lids yet) in the pressure cooker like you would normally on a rack with water. Process with petcock open and exhaust the cooker for 30 minutes. Remove the jars and put the seals on immediately. Adjust the lids to tight. Process in the cooker at 10 pounds pressure for 75 minutes.
These old canning books are becoming important again as people are beginning to see that all the processed crap we've been used to eating is killing us and making us fat. Nice to see people getting 'back to the land'.