(See the best response by Lige.)
icon = 'Bigteleporter2013.dmi'

Problem description:
I want to move it by pixel_x - 16; to align it in the center instead of it coming off on the right a little. If anyone can help me with a code that can do that; I'll be grateful.
Best response
If you're just looking for visual alignment, you've already answered how to do it.

icon = 'Bigteleporter2013.dmi'
pixel_x = -16

Edit: Although, that might have undesirable effects on your map since you're using /turf. Might want to use /obj instead.
In response to Lige
Thanks a lot, I've been a little rusty lately ^.^