This How-to describes the process of modifying the timing plate to allow for up to 4-degrees of advance.
1. Remove timing cover.
2. Remove center bolt. This is probably going to be very tight. If you do not have the grinder disc tool mentioned in the above post, a 6" c-clamp will work well if you're very careful. You'll have to get the clamp very tight, perfectly in line so that it won't slip off, and get a good grip on it so that it doesn't bash the timing sensor. A 1/2" drive breaker bar is necessary (or a pipe on the end of your socket wrench) to get enough controlled leverage on the center bolt. After the center bolt is loosened, it should back out with your fingers. The timing disc will come off easily.
3. With the timing disc removed, remove the bolts holding the sensor plate. These are JIS screws, and are probably very tight, either because they've been in there since the bike was built, because they're secured with Loctite, or both. You will need a #2 JIS screwdriver and/or an impact screwdriver, as the heads WILL strip out if you attempt to do it with a Phillips scewdriver.
Carefully remove the sensor from the plate (not much room to play with the sensor wires) and gently pry out the sensor plate.
4. Using a protractor, measure 4 degrees COUNTERCLOCKWISE from the center of the existing bolt holes (NOT the holes that the sensor is mounted to the plate through or the alignment hole). Mark that point. Four degrees counterclockwise from the center of the existing bolt holes will be the new center hole. It just so happens that 4 degrees is one radius, so the new bolt hole will be centered on the edge of the existing one.
Note: In the above photo, I'm measuring on the back side of the sensor plate for reference only. The new hole is not drilled in the position in the picture.
5. Using a drill press, drill the new hole. The bolts are M6, or 6 mm in diameter. Carefully file out the new hole so that the new hole is continuous with the old one. Remove all burrs and then clean with alcohol to get all the shavings off.
6. Slip the sensor plate back in place and mount the sensor to it.
7. Rotate the sensor plate CLOCKWISE by NO MORE THAN 4 DEGREES. Because 4 degrees is 1 radius of the bolt hole, it's easiest to do this by measuring the distance from the center of the bolt hole on the engine relative to the edge of the bolt hole in the sensor plate. The center of the bolt hole on the engine will need to be one diameter from the edge of the original bolt hole in the sensor plate.
To reiterate, the sensor plate should be rotated so that the edge of the original bolt hole in the plate is now one bolt width (~2.9 mm) clockwise from the center of the bolt hole in the engine.
8. Bolt the sensor plate back into place (70 in-lbs).
9. Bolt the timing disc back into place (32 ft-lbs).
10. Bolt the timing cover back into place (86 in-lbs).
As mentioned in the previous post, take a test ride, listen for detonation. 91 octane fuel is recommended to prevent detonation.