Oil light flicker

my 71 challenger had same problem. it never gave me any problems. but i decide to rebuild my tranny and remove the oil pan to check the rear mains and rod bearings. the man that sold me the car thought the engine only had 23,000 miles on it. the car was real clean. well, i found the flickering light problem. the rear main bearings were already worn down into the babbit material of the main bearings. i replaced all lower end bearings and flicker problem went away. good luck,
KUHL DART