I think gamboa would win. Luevano had a luckluster fight with the c- class fighter in jandaeng. You would see at that fight how jmm's skills is really topnotch (he also fought jandaeng and destroyed him) compaerd to another good technical boxer in luevano, not that i'm downgrading his skills, steven is pretty scientific but he has suspect stamina, a weak breadbasket and his workrate just fades at late rounds.
He also had a luckluster fight against mario santiago: who lost to a c+ fighter inhector velasquez, also a former foe of pac.
Yuriorkis on the otherhand, a known slugger, had an impressive 1st rnd tko win against al seeger.
Because of luevano's lackluster wins which he struggled against fighters like santiago and jandaeng, i'm leaning more to gamboa winning this by a mid to late round stoppage. Possibly by rnd.9. tko.
Who do you think would win?