Well, this is aimed at the GT but may apply to others.
If you have dogbones and get sick of them throwing out those crappy little red o-rings, get pvc washers like are used in water hoses. Use a hobby knife to cut off a small piece of the tree that the washers come on and use it in place of the o-ring. Just trim it so that your dogbones have the right spacing. It's large enough that it can't be thrown out of the outdrive/axle, so problem solved.
Or... you could just get CVDs
