I don't read internal temps on beef or pork ribs. Are you doing a rack or individual ribs? I know that medium rare is around 140*, medium 160*. Basically I watch for colorizing of the meat and the meat pulling back from the rib ends.
Of course using 3-2-1 takes the internal temps out of the question anyway. I have had some beef bone ribs done in 3 1/2 hours.
Rumor is that it can ruin the probe but I don't see why? Makes sence that the metal on the grates could be a problem but bones? I use dial thermometers there easier to deal with. Although I have 3 digitals for some reason. It will definately mess up your reading though. Good luck and enjoy!
Since the bone can be warmer than the meat, it can give you a wrong temp. There is just so little to work with on ribs. Trust your 3-2-1, then if you want something different for some reason, just adjust your 2 or 1 setting to get your desired results.