[Elecraft] KPA1500/PS SPACING

[eric norris]

Gangue:
I am considering a new shack layout that would place on a single shelf, in left to right order, KPA1500 RF DECK--HW-16--KPA1500 PS.  My question for the brain trust is:  How much space is required between components?  The PS cannot go on the floor at this point.  The KPA1500 and HW-16 are not being operated at the same time, obviously.  The K4 is on a lower level and is not a factor.
The KPA1500 components will not be up on their bails.
Thoughts?  Thanks and

73, Eric WD6DBM