I believe this is about 7th time I have had to state, that Olmecs including their heads are found only in Mexico, especially at just one site called La Venta. This is near Veracruz, and Olmecs are sometimes stated to have occupied the Gulf Coast lowlands around the area from Veracruz to Villahermosa. At the very widest.
I'm guilty, you're correct. (again) I can't seem to get the thought that they are in Brazil out of my head.