longer PSU Cable ... please look-..

Hi,
I currently wanna have a longer power supply cable on my AT PSU - So i looked up the pinout for AT and noticed that there is many times 5v , 12 v etc with a total of 6 diffenrent Voltages ( GND included) So my question is - Can I put only one cable for each Voltage (&gnd) from PSU to PC case and then reconnect the one wire to the different with same voltage on Motherboard connector ?

( PS: Its for my internet router which has to fit in a very little case and so no place for PSU which has to go under the desk :) - Its a 120MHz Pentium with a LAN , and a ISDN crd ( no Grafic crd!) and a floppy drive so I think it wouldnt draw very much current ?! ) :confused:

Many Thanks

Felix

P.S: I did my best to explain me as comprehensive as possible ;)

Try opening up the supply and remove the PCB. That way you can check which wires are actually linked on the board. If they go to different components it's best not to link them.
Best regards,
Matthew