Lightbulb port ics update to gb device

how can i port the ics update to gb android bcoz official update are now imposible
i want to port ics update to my karbonn a1+

karbonn a1+ specification :

2G Network {not 3g}
SIM Dual SIM (Mini-SIM)
Size 320 x 480 pixels, 3.5 inches
Internal 256 MB RAM
Camera Primary 3 MP, 2048 x 1536 pixels
Secondary Yes, VGA
Features OS Android OS, v2.3.6 (Gingerbread)
CPU 1 GHz
Sensors Accelerometer, proximity
Radio FM radio
GPS No

plz provide me source or any other help
i am not totaly noob so i can understand