Blinky eye texture help

Sorry to bother anyone with this though I apear to be having trouble making the proper texture for making eyes blink onto a sphere,

I know how to make eye textures themselves, its just the distance they would have to be on the texture that is confounding me again and again. some of the things I've tried has made it so when it blinks it goes into itself, pretty sure it isn't the script,

if anyone had any help or tips for making a decent template for blinking eyes I'd be very greatful, ^-^