A good t shirt might be
GAS GAS words on top of the shirt
with a pic of an orange sheep with a red circle with a slash through it, over the sheep. In the middle of the shirt
and then the words
No sheep, Don't be a Sheeple or don't be a sheep
Or maybe "Be the leader, not a follower"
on the bottom
Of course that might be somewhat confrontational with big orange!
While I'm ignorant of what Franco and the spanish revolution was all about it might make an interesting tie in with the orange sheep thing .. kind of a "Free the sheeple" campaign
hmmm you could do some interesting things from a viral marketing standpoint with an orange sheep.
Pic of some orange sheep in a field with a wolf in dirt bike gear, sitting on a gas gas of course, with a "this is going to easy look on his face" parked at the edge of the woods. maybe add the words ..."Who would you rather be!"