A La engine is any small block chrysler up to 1991. Switched to magnum after that (different heads and valvetrain oiling). As for a 76 to 80 360, probably painfully low compression with smog heads. But all that can be rectified in short order.
Not quite true. The LA series engines evolved from the A series small block (i.e., 318 and 325 polyspherical engines). The L stands for light which was a redesign o he block to take out weight.
So a 318 up through 67 is not the same as a 318 through 91.