Here are some tips on grilling ribs that I heard. Always cook on INDIRECT heat. You could cover the ribs with a cake pan to help trap in more heat. To test for doneness do the wiggle test. Grab one of the bones and give it a wiggle and if the bone pulls away from the meat they are ready to eat. One more tip, a good rule of thumb is to buy 1 pound of ribs for every person you will be serving. Baby back ribs will have more meat on them.