Ok, first let me apologize for not posting pictures. I am sadly without a digital camera (or any camera for that matter) so if anyone can get the pictures I will post them and complete this thread. Now for the mod:
Mod: A "turbo" green button.
What it does: Simulates holding the green button down.
Purpose: Play five buttons with four fingers and without moving your hands.
Simple Toggle Switch
1. Find a place to mount the switch. I put mine in the extra strap pin hole on the bottom of the guitar but you can place it wherever it feels comfortable.
2. Open your Rock Band guitar. Not too hard but a bit time consuming. Make sure to take the fret board apart as well.
3. Find the circuit boards behind the buttons and remove the screws to remove them.
4. Trace the wires down to the controller's main board and unplug the connector.
5. Find the blue wire in the center and the brown wire on the outside next to the black wire.
6. Use the Xacto knife to carefully cut the two wires from the ribbon.
7. Use the wire cutters to snip each wire and strip a bit of shielding off each end.
8. Now take the toggle switch and solder a wire lead to each switch lead Make sure to leave enough to run to where you are going to mount the switch. (Mine only had two).
9. Solder the leads to each wire while also soldering the wire back together. So at this point you should have essentially a switch spliced into each wire.
10. Cover each of the solder joints with some electrical tape so as not to cause any shorts.
11. Reattach the plug and test the mod out. If it works, mount your switch and reassemble the button boards.
12. Finally, reassemble your guitar and start playing.
Alternate Mod: Use a momentary switch and mount it on the back of the fret board just where you would place your thumb. Now you can hold the green button down with your thumb and accomplish the same thing as above.