i found him. but he's not IN Cumana. my favored method of finding a bounty is by
helicopter because it's faster. when in cumana. call in a helicopter if you have one in
your stockpile. or steal one. Travel south of main cumana along a dirt road until you
reach the end. he should be there. if that didn't help. here's a map,

http://www.gamefaqs.com/console/ps2/file/938443/54216

try going south of cumana!

carefully when you attack General pena . he command multiple armored tank , but if you
using diplomat heavy tank can destroy pena's tank , you can disguise too if you not
spotted officer/Gn.pena.