Guitar Hero

SG Guitars (PS1/PS2)
Screw type: Phillips Head

Xplorer Guitar (360/PC)
Screw type: Phillips Head (if released packaged with Guitar Hero II), otherwise Torx (if released with Guitar Hero III)

Les Paul Guitar (360/PC/PS3/Wii)
Screw type: Torx

Frets Dropping
The most common issue with the Les Paul is that the frets drop/flicker when held. This is due to the poor design of the detachable neck. There are two ways to fix this: solder the detachable neck to the mainboard of the guitar (guide coming soon), or fold a piece of printer paper and insert it between the base and neck to tighten the connection. Guide

World Tour Guitar (360/PS3/Wii)
Screw Type: Torx

Guitar Hero 5 Guitar (360/PS3/Wii)
Screw Type: Torx

Warriors of Rock Guitar (360/PS3/Wii)
Screw type: Torx