COPO 9511

[69L72RS]

Here are a few clarifications. Sorry, I was in a hurry when posting earlier.

The "9511CB = 4.88 (3862528-3862516)" is from a Z28 not a L72 Camaro.
The 3862528-3862516 set is the standard duty gearset for a BX coded rear.
To the best of my knowledge the 4.88 was not able to be ordered with the L72 cars under any code.

The HD 4.88 gears were over the counter only (3916232-3916233)as
part 3917972.

The 9511DT code is from a factory ordered L72 Camaro with 4.56 gears [(3916230-3916231)set number 3917973].

Also, the "BW" axle cars that I have had in the past were rear drum brake cars.
The 4.56 ratio JL8 axles that I had were all "QZ" coded.
The rear that is pictured doesn't look like any JL8 that I have ever had.