If it's a 9" chunk, It'll fit into any other 9" housing provided the axles match (the spline count). I used to have an axle decoder chart downloaded off the net, but don't recall what I did with it. might do a search for one.
2LA 75 should be the gear ratio.
2.75 'L'imited slip.
But what does the 'A' stand for?
I don't have a book or anything, so I can't help much...
I am just using what I know, which is just enough to get me into trouble.
Dave
Your axle WES-T is a 2.75 ratio 9 inch. Are the codes on the tag as you have listed them with 2LA on the top line. Ford has changed it's tags about five or six times. The axle I believe would most likely be out of a 1968 Mustang. By the way the casting number on the case would also help. Best way to check the fit would be to measure flange to flange, and measure Spring pad spacing. The typical axle width for 67-70 mustangs was 59.375 inches(flange to flange) with a pad spacing of 43 inches (center to center). Note that these are typical, and you shoul always measure you application.