95 Thunderbird rear end gear

Need to know what is the correct rear end gear for 95 Thunderbird with 4.6l V8. Has 3.55 in it but it's not the original and we were told it needs a 3.08 gear. Which is right

look inside the driver door jam for the codes and let me know what the code is below the axle identifier ( AX ) and I will post which gear your car came with: Y is a 3.08 2 is a 3.55