Can I back up and ask if this is the L or K case type?
L I think represents low
= 1 * height of the operators/programmers panel.
K I think represents bigger (King Size?)
= 2 * height of the operators/programmers panel.
As an introduction, mines' a K (maybe no -A- type tho)
and the PSU represents about 1/3 of the volume;
1/2 of the weight.
(IIRC) John A.