I have almost 2 pounds of uncooked short rib bones (I cut them off short ribs  then froze them). There is very little meat, if any, on the bones. Am I able to make beef stock using just these bones? Should I add one of the small marrow bones I have in the freezer (I don't want it greasy) or buy different bones? Or do I also need to add meat to have a tasty stock that will 'gelatinize'? In other words, are short rib bones enough?  I've made chicken and turkey stock countless times, but never beef, so I am truly clueless. I generally don't add meat to a chicken stock, just whatever little I haven't cleaned off the carcass, and wonder if I would get the same good outcome with just beef bones. I have read this question, but it doesn't address my question of short rib bones. What bones for beef stock. This question Making Beef Stock, while telling me HOW to make the stock, doesn't tell me if short rib bones work. Thank you. 
Yes, you absolutely can make stock from the bones.  In fact, I used to be a bit mystified at people using "meaty" bones, since I first read about making stock from the bones.  The method for making this kind of stock calls for "bare rendering" bones - with almost all the meat removed.  The marrow and any connective tissue supply most of the flavor.  To strengthen the flavor to offset the lack of meat, you roast them in the oven first (which is a good idea, even for meatier bones).  In any case, your accumulation of the short rib bones with almost no meat on them would be a perfect fit for this recipe.  I was able to locate that first recipe for making beef stock that I referred to - from the Frugal Gourmet:  Frugal Gourmet - Basic Brown Soup Stock 