How do I install female XLR's in Aragon amps?

Long ago I bought two Aragon 8000-series amplifiers with RCA inputs but with blank ports (plates with screws) to allow installation of balanced XLR jacks (female, I presume). I just bought a Krell processor with balanced XLR output, but unfortunately, Aragon has gone out of business and I can no longer find a dealer to convert the amps to XLR. I would rather do it myself by purchasing Neutrik jacks and soldering the wires.

The problem is that I do not know which wires on the RCA jacks to solder to the XLR's. I assume that the outer-shell RCA wire (ground or female) is to be attached to the ground lead of the XLR and the center RCA wire (signal or male) is to be attached to the positive lead of the XLR. Is this right? But where do I attach the third XLR lead in the amplifier? Is there a shield wire? To the chassis?

Aside from the wiring problem, will I have a problem with a larger input voltage or any other unforeseen problem. If Aragon provides the port, I assume not, but I'm not sure. Please help!
DO NOT BOTHER installing XLR's... just get either XLR to RCA cables or get some Cardas XLR to RCA adapaters.

Modifying the amplifier will reduce the value also. The other option you could do is to sell your current amp and buy another amp with XLR connectors. But just because a piece has XLR adapters doesn't mean it is a fully balanced piece of gear. If the item isn't truelly balanced than RCA to XLR adapters will provide the same level of performance.
he is correct sounds like your amp is not truely balanced so dont waste your time it wont make any difference
The reason why you don't know where to put the third wire is because you would need truly balanced (differential circuitry) with a +, -, and ground. I disagree with cytocyle on the mod significantly reducing the value because the ports are already there, but you won't get a fully balanced signal chain. I do agree with him that an XLR-RCA cable will accomplish the same thing, but those are not cheap and have pretty limited resale value (I know). If you go the cable route, make sure you verify which pin in which on the Krell. there is a common but not universal standard.
The 8008ST will have a plate but no XLR jack. The 8008BB has both RCA and XLR input jacks; when the RCA jacks are used, a tiny jumper is inserted into two of the three ports in the XLR jack.

A Palladium II or Palladium 1K uses the same basic layout as the 8008; but is set up internally to be a true balanced design; and is a single-channel (monoblock) amp.

I'm using a pair of RCA-to-XLR adapter plugs on my Palladium IIs; using XLR-to-RCA adapters on your system is probably the simplest, cheapest, easiest solution if your Krell processor doesn't have RCA outputs.

First Guess: if you have reasonable-length interconnect cables, you won't hear any improvement from the balanced connection.

Another option is to sell the 'ST and buy a BB version; you gain the factory-installed XLR connectors along with additional power supply, larger storage capacitors, and 50% more output transistors.
I finally received some good teflon-coated wire (OFC with high silver content) and installed new Neutrik XLR female jacks. The XLR posts, as labeled on the jack chassis, are for:
(1) Shield wire;
(2) Non-inverted-signal wire;
(3) Inverted-signal wire.

The wires are soldered to the RCA equivalents, as follows. The shield wire (1 above) and inverted-signal wire (3 above) are jointly connected to the RCA ground (negative or outer chassis). The non-inverted-signal wire (2 above) is connected to the RCA positive (or center).

Once the wire is soldered to the XLR jack posts, there are two ways you can attach the other ends of the wire to the RCA circuits: (1) Use short jumper-wire lengths from the XLR jack andsolder directly onto the female RCA leads along with the preexisting wires on the RCA (leave them intact so the RCA's can still be used if you sell the amp or want to use them later); (2) Use longer wire lengths and solder the XLR wires directly onto the circuit board (leaving the RCA wires intact); if the solder points are not labeled positive (+) and negative (-), you can determine which is which by tracing the wires from the RCA jacks. I prefer this method because it allows the use of upgraded wire and is more direct to the circuit board. If desired, you may 3-way braid the XLR wires before you attach the XLR jack to the amp chassis.

If you use the RCA jacks, you will NOT need to insert a 1-3 jumper wire into the XLR jacks because the input circuitry is not truly balanced. As for the question of whether it is worthwhile to install XLR's this way, it depends on a variety of factors. First, if you do not have preexisting ports for the XLR jacks, you will have to drill large holes for the jacks and small ones for the mounting screws (they do not have to be threaded if you use small nuts to secure them). If you have the ports (like my Aragon amps do), labor aside, you can attach two high-quality XLR's for less than $15 and get a better connection, compared to using XLR-RCA adaptors, which cost about $20 each for good quality. For short, shielded interconnectors, the increase in gain and sound quality with the XLR installation will be small, possibly negligible, considering how much gain in quality is needed to keep it noticable after acclimation. Face it, if you have to do a direct A-B comparison and study the difference in sound quality, there isn't a meaningful difference. If you can easily tell the difference by memory, there is. Anyway, I hope this discussion is useful for those of you that might want to add XLR's to amps with non-balanced inputs. Thanks to those who contributed to this discussion.