This is good info and I'm going to paste this into the Customize your own Oakley thread since it is likely to come up again.Ok, here is a breakdown on just a few of the common swaps that can be done, if you need something specific just ask.......
Juliet earsocks fit: Juliet, Xmetal XX, Romeo, Penny, Mars
Juliet temple shocks fit: Juliet, Xmetal XX, Romeo, Mars
Juliet nose bombs fit: Juliet, X squared
Xmetal XX Earsocks fit: Xmetal XX, Juliet, Romeo, Penny, Mars
Xmetal XX temple shocks fit: Xmetal XX, Juliet, Romeo, Mars
Xmetal XX nose bombs fit: Xmetal XX
Romeo 1 nose bombs fit: Romeo 1 and Mars
Romeo 1 earsocks fit: Romeo 1, Juliet, Xmetal XX, Penny, Mars
Romeo 1 temple shocks fit: Romeo 1, Juliet, Xmetal XX, Mars
Romeo 2 Earsocks, temple shocks, and nose bombs fit: Only fit Romeo 2
Penny earsocks fit: Penny, Juliet, Xmetal XX, Romeo 1, Mars
Penny nosebombs fit: Penny
Half X earsocks fit: Half X
X squared earsocks fit: X squared
Xsquared nose bombs fit: X squared, Juliet
X squared tempe shocks fit: X squared