Since I am so grateful for the work put into this project and I like to give back the community, I will type a quick step-by-step guide for those that were asking for one.
This mod requires you to open your hardware and to solder on the board. If you are uncomfortable with desoldering/soldering or unwilling to risk frying your router in the process, this mod may not be for you. If you are like me and had one lying around because you upgraded the piece of crap with something better, then have at it.
There are really only three steps, but they are a little involved.
1) Build a JTAG cable
This is outlined in the earlier posts, but all you need to do is follow these diagrams:
You will need:
1 - Male DB-25 Connector (with solder cups)
4 - 100ohm resistors
1 - 5 to 12 wire ribbon cable (only 5 wires will be connected)
1 - 12 pin connector
1 - 12 pin header
The pictures of the actual cable in the pdf posted earlier are reversed so just follow the diagram above. My DB-25 connector was labeled with pin numbers next to the solder cups. From the back (looking at the solder cups) it looked like:
Once you open up the case of the MN-700, you will find the pin numbers for the JTAG port are printed on the board so it should be pretty easy to follow. The finished cable should be no longer than 25cm or about 10 inches, otherwise you will have too much noise in the line. You can use a parallel port extension cord to reach the back of your computer, but I just pulled out my computer and piled up some reams of paper to support the router while flashing.
The last thing, and most time consuming for myself, was to clean out the JTAG port holes on the board and solder in the 12-pin header. You need a soldering iron and either a solder sucker or solder braid to clean out the holes.
Once you have all of this done you are ready to move on to the next step.
2) Use cable to backup/flash bootloader
First you need to get a copy of the modified bootloader from Oleg. Send him a private message with your MAC address of the router and he will hook you up (and make sure you thank him).
Now you can use software either under Windows or Linux. Using a Linux distribution will flash about twice as fast compared to windows, but either work. Since I had to use Windows, as I am sure a lot of people will, I will outline that. First get a copy of your software, which I have mirrored.
Windows
Linux
In windows extract the zip to a known location. Then go to start > run and type "cmd" and hit enter. This brings up the command prompt. Browse to the directory you unzipped to and type "wrtjtag-modified" and hit enter. It will display all of the options and switches to use. For example you will want to backup your bootloader from the router in case you run into trouble. To do this type
Code:
wrtjtag-modified -backup:cfe /noreset
Connect the JTAG cable and plug in the power to the router, then hit enter. It will start to backup the bootloader. If you get an error you've built your cable wrong.
Next you need to flash the bootloader you obtained from Oleg. Place it in the directory you are running the program from and rename it to "cfe.BIN". Type
Code:
wrtjtag-modified -flash:cfe /noreset
Once you hit enter it will start flashing the new bootloader onto the router. If it completes successfully, continue on to the next step. The hard part is over.
3) Flash new firmware with ASUS firmware utility
Head on over to ASUS website and download the utilities package for the WL-500. Included is a firmware restoration tool we will use to flash the new firmware. You will also need the firmware you are planning on using. I used the 1.9.2.7-5 firmware found on this website. You will also need to turn off all network devices except for the one needed to connect to the router (disable them in the device manager).
Install the ASUS utilities and open the firmware restoration tool. Click "Browse" to tell it where you downloaded your firmware to and hit "Open". To start the firmware update click on "Upload". Once completed you will have a brand new "WL-500g". Hope this helps! Good Luck!