You mean changing the skin? you need to look in descr_model_battle in the EB data folder. You'll see something like this.
Code:
; Iberian infantry - Loricati Scutari -------> MISSING MED/LOW/LOWEST
type iberian_infantry_loricati_scutarii
skeleton fs_javelinman, fs_swordsman_barb ; throwing spear
indiv_range 40
texture spain, eb/data/models_unit/textures/iberian/ebiberian_infantry_loricati_scutarii_aymar_spain.tga
texture egypt, eb/data/models_unit/textures/iberian/ebiberian_infantry_loricati_scutarii_aymar_egypt.tga
texture slave, eb/data/models_unit/textures/iberian/ebiberian_infantry_loricati_scutarii_aymar_slave.tga
model_flexi eb/data/models_unit/ebiberian_infantry_loricati_scutarii_aymar_high.cas, 15
model_flexi eb/data/models_unit/ebiberian_infantry_loricati_scutarii_aymar_high.cas, 30
model_flexi eb/data/models_unit/ebiberian_infantry_loricati_scutarii_aymar_high.cas, 40
model_flexi eb/data/models_unit/ebiberian_infantry_loricati_scutarii_aymar_high.cas, max
model_sprite spain, 60.0, eb/data/sprites/iberian/ebsprite_iberian_infantry_loricati_scutarii_spain.spr
model_sprite egypt, 60.0, eb/data/sprites/iberian/ebsprite_iberian_infantry_loricati_scutarii_egypt.spr
model_sprite slave, 60.0, eb/data/sprites/iberian/ebsprite_iberian_infantry_loricati_scutarii_all.spr
model_tri 400, 0.5f, 0.5f, 0.5f
just copy the Luso's texture and sprite addresses over the carthaginian ones. You might want to change the unit icons as well.
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