ANY REAREND EXPERTS ?

[KEVINJJOHNNY]

I am installing a Mark VII rearend into my 91 Mustang. I Need help identifying the small plate attatched to the differential cover.Here it is below.
S 4 0 7 F
3 L 2 7 N 8 8 8 0 0 7

If anyone could help me in identifying this it would be much appreciated. Thanks

 

[10HoleLX]

The ...3L27...equals to this:
3 27 gear ratio
with a limited slip,
thats what the L stands for