You may want to just put toothpicks in each one (one pick for rub 1...two picks for rub 2..etc). I use wood skewers to hold the ribs in a circle and they stand up fine...I can't imagine toothpicks would be much different. Bunch them together so they don't get in the way.
Just a thought... Let us know how the rubs/sauces combo came out.
Enjoy!