[morzh]

I have a question about replacement of the 5 capacitors inside the metal box, 7A,B,C,D,E.  Shall I assume these are shielded inside the metal box for a reason?  

Instead of running all the wires back to the metal box, why can't I just solder in replacement capacitors near their connection points with the other end of each going to the nearest ground point?

Thanks,

Mark

Mark,

Yes it is possible and I do not think the can is intended as a shield.
However, if you solder caps to nearest GND you may or may not have GND currents and so some extra noise.
Not necessarily, quite posible it might be just fine.
There is even a chance it will work better as then you need no long wires for some caps which are inductive and so themselves defeat some capacitance and introduce extra noise. The experiment will show if it is better, worse or the same.