Hi Ritche! Welcome to the club!
Beef and pork ribs can certainly be smoked together. Use 235 for the set temp, with a pan of juice or water next to the smoke box. You can pull the beef ribs sooner than 5 hours - beef can be medium or medium-rare, unlike pork. Check out the Pork and Beef sections, in recipes, for particulars on each, and use some judgment on when both are done.