Would it be possible to replace the 2-prong cord of my old DS5 with a 3-prong cord?
 
The current power cord is extremely dried out, and I'd like to refresh it with something new, but I'm not sure what I need to buy.

Shouldn't be too hard. A lot of times when I need a new line cord, I'll just cut the end off an IEC cable, as I seem to have tons of those lying around. The third wire is a ground and it should be pretty obvious if you open up the power supply where this goes.
 
One thing, in what country are you located?
Edwin

Edwin; Chris is in Ohio.

OK, being in the US myself, I didn't know if there were other issues in other countries, so I didn't want to offer advice that might get someone electrocuted.  
 
I've built a few of these, but I don't recall off the top of my head exactly where I put the ground wire from the line cord, but as I said, it should be obvious where the main ground is once you get in there.
 
I think it also wouldn't be a problem to replace it with another two wire cord. Good grounding is obviously better, but you should be fine either way.
 
Edwin

Hmmm.
 
Well, that certainly works as far as sourcing the cord, although I can afford to go a little fancier than that. ;-)
 
I guess my real question is-how should I wire it? Looking at the innards, there's no ground immediately apparent-just two wires from the primary side of the transformer, wired to the cord with wire nuts, and bridged with another thicker wire. From the secondary of the transformer, there's a green wire and a red wire going to the caps, and a yellow one going to the Bass/Mono jack.

Without seeing the inside, I would guess at attaching the earth(ground) to the chassis with a fixing lug, basically if some component or wire touches the chassis it will go to ground rather than you.
I always back everything up with a RCB anyway

RCB?
 
Royal Canadian Beer?
Really Crazy Bush?
Red Cocobolo Bass?
Radical Cocaine Buyer?
 
O.K., I'll bite.
 
Bill, tgo

Bill Residual Current Breaker, as we know them over here in the UK  
Mind you all of the above are okay

Hm, sounds like an aardlekschakelaar to me. No house should be without one (unless its a defective one).

Is this the same as a GFI (ground fault interrupt)?
And if not, what is it? Should I have one?  Am I born with it, or do I need to run out and buy one? HELLLLLLPPPPPP!!!!!
 
Hey, is this just another way of saying circuit breaker like the ones built into my power strips?
I GOTTA KNOW!!!!!!!
 
Bill, tgo

Device that measures the incoming and outgoing current (in this case, for your entire house). If there's a big difference, there must be a short-circuit, and the device cuts off electricity instantly.

Do we have such a device in the U.S.?  What's it called?
 
Bill, tgo

Bill,
 
RCB's are the same thing as our circuit breakers.

Bill,
We call them GFCI or GFI breakers/outlets in North America.
 
Keith

 
Here's the innards.
 
If I understand correctly, then, the ground simply needs to be affixed to the chassis?