Hi Dieter 

Thanks for the advice,

What I actually need is to build a case with a Doepfer PSU2 and connect a Mean Well S-40-5 (+5v) output switching power supply to add a powerful +5 to it , this is in order to use 3 x Metasonix r55 modules that suck a lot of +5v. I also wanted to have independent power switch for it (as they draw a lot of power ) so thought in a 3u case , BUT NOW i realized that one of the two back panels in a G6 case (the top one) can be removed and replaced with a a-100 b84p , that has the PSU2 already installed, then un-plug the top bus board and connect it to the top PSU2 (the one that also has to be upgrade with the Mean Well +5 v . That way I can have a G6 case with two PSU each one with it's own power switch and fuses and it's own bus board. The top part for those tube modules. 
I can ask a technician to do the job for me.

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