I'm going to comment on my own question. Don't add the green beans. They will turn to mush! I can add the green beans when I open the jar and heat them with the stew. However, I would like to know if I reduce the ratio of veggies to meat AND keep the total volume the same (7 qts) by adding extra liquid, will this be safe? It closely matches the a beef stew recipe approved by the Wisconsin safe food preservation series discussed elsewhere on this site. Maybe I should just go with that since it has almost the ratio of veggies to meat we like.

You can always reduce or leave out any low-acid ingredient (like the potatoes) as it only improves the safety (raises the acidity level and reduces the density) as long as the amounts of the other ingredients remains the same.

The safety issues arise when you try substitutions or increases of the other ingredients because both can negatively affect both the pH and the density.

So in your specific instance: "So if I cut the potatoes to 6 cups each, add 2 cups cut green beans, drop the carrots and celery to 2 cups each, divide this equally between 7 quart jars and fill with liquid from boiling or tomato juice would I be in danger of not having a properly processed jar? "

No problem except you couldn't add the beans. The only problem would be if you tried to increase any of the other ingredients.

Dave