Not just one person has approached me to inquire about my project and to volunteer the idea that their family may be Spanish because there is a town in Spain with the same name.
I told them Carcar itself is a name of a town in Navarra in Spain.
And that: Abella, Aguilar, Alcántara, Alcobendas, Alcorcón, Alcorisa, Alcover, Alcoy, Alcudia, Alcuetas, Alday, Aldaya, Aldea, Aldosende, Aldueso, Alea, Aledo, Aler, Alera, Alerre, Alesón, Alfáfara, Alía, Alicante, Altafulla, Alvarado, Ávila, Avilés, Barán, Baranda, Barazón, Barbadillo, Barbecho, Barca, Barcala, Barcelona, Bárcenas, Barcenilla, Barcia, Barcones, Barrañán, Barranda, Barrasa, Barruelo, Bugarin, Caballero, Cabanillas, Camos, Camuñas, Cañada, Cañedo, Canencia, Cañete, Castañares, Escóbedo, Fano, Génave, Jaén, la Bastida, Lavapiés, Ledesma, Llanos, Machacón, Martillán, Montecillo, Montesclaros, Nadela, Nava, Navares, Nemeño, Nemenzo, Obeso, Pastoriza, Peña, Quijano, Rodis, Silva, Tanos, Tapia, Tora, Torres, Valencia, Vélez, Villanueva, Zafra-- and probably others–are all towns in Spain, too.
Any claim is really very easy to settle. Just remember that Spanish-descended families not only had their surnames well before the 1849 Claveria decree, but since the church records always included racial classifications, also had the classification of either Español or Mestizo Español. So, sorry, if your family did not already have the surname before the decree, or was not classified Spanish–except if they had Spanish blood through an unrecorded illegitimate father–grind, pardon the pun, and bear it; we were indios. Padre Dámaso: noli nos tangere.