Troops of the Nigeria Regiment, 3rd West African Brigade (Thunder), boarding a Dakota Transport
“In 1943 the 3rd (West Africa) Brigade was detached from the 81st (West Africa) Division, and assigned to the Chindits as a garrison force for the jungle bases established by the Columns. The Brigade comprised of the 6th, 7th & 12th Nigeria Regiments. These were African soldiers lead by British Officers and Senior NCOs, and contained Nigerian Other ranks, and Junior NCOs.  They fought with distinction with the Chindits, and caused a number of the Japanese units to flee as a result of their ferocity.
Their fellow force members from the 81st (West Africa) Division fought in the Arakan alongside the Essex and other Regiments, these other African Soldiers also included soldiers from Gambia, Sierra Leone and the Gold Coast”
http://www.farsettingsun.co.ukRoyal West African Frontier Force’s Nigerian Chindits
Beegeagle's Blog 
Am researching my dad’s service with Royal West African Frontier Force and with the Chindits in1944. He was probably with 3 West Africa Brigade. Can you point me towards sources of info which may clarify his service?
3 Brigade was a formation under 81 Division of the West African Frontier Force. It was a Nigerian contingent which had 6 Battalion, 7 Battalion and 12 Battalion under command.
In which of those units did your father serve? That could be our takeoff point.