MF MA 50 Monoblocs - dealing with heat.

[donkeytrousers]

I have just bought a pair of these wonderful amps second-hand. I have been reading-up on line and have started to concern myself with heat dissipation to avoid long-term reliability problems.
As these amps have holes (grilles) on the left and right cheeks and a ridged heat-sink as the top plate, it occurred to me that if I mounted them vertically (instead of the normal horizontal fashion) I would create a natural up-draught of warm air both through the middle of the amp and also across the top-plate. It seemed to me this ought to be a more efficient cooling method that leaving them horizontal. As a bonus,it would also ensure that nobody could place anything on top of the unit, prevent the heat from dissipating.
I wondered if anyone else had had this flash of inspiration/madness and tried it?
Any views?