rear end

i just pulled my 10 bolt rear end of my 69 bird and got some numbers off it there was a 1254333 and a 271 and GM 33 but did not come with anything when i ran the numbers if any one could help thanks.well i pulled off the cover and counted the ring gear and pinyon gear 41 on the ring and 15 on the pinyon gear and if i divided it right i think its a 2.73 so to make sure if it was a 8.2 or 8.5 i heard of counting the gruves were the yoke comes off an 8.2 has 25 to 27 and an 8.5 has 30 but not sure if you can go by that or not i came up with 30 on mine.if anybody could help thanks.

Sorry, but I refuse to help someone who is too lazy to even spell the name of their car right.

Abe <---who is dyslexic and can still spell Firebird