Frenzy/Rumble
Personally, I go with the toys. So for me, Frenzy is blue...
...and Rumble is red. However, if you don't think so, then I did a simple cut job for you. I believe someone has already done this, but I need to pad out my site. :)
Credits
Base Tech images: Rumble/Frenzy Tech Spec from the International Transformer Tech Spec Archive