I was just going ask the same question.
LA is probably the same tube and stick.
6 quarts should be more than enough of a safe range on any LA or A engine. Only issue I would be more concerned about is whether the pickup is correct for the pan and that the pickup is low enough in the pan. Most engines will have the pickup about a 3/8" or less off the bottom of the pan, you don't want it to high to become uncovered.

Mark D.

1968 W200 Sweptline
1969 D100 Utiline
1971 D100 SE Sweptline
1993 D250 Club Cab Sweptline
1986 W250 Cab & Chassis
1978 D300 Sweptline

E. Brookfield, Massachusetts