My video guide on how to disassemble a sig 552.
Here is a guide on the V3 mechbox:
http://www.mechbo x.com/site/mechbox-u pgrades/version-3-me chbox-upgrade-video. html
Here is another Disassembly Guide:
http://www.858air soft.com/howtos/sig5 52disam.html
Here is another guide:
http://www.airsof thacks.com/2007/11/t m-sig-552-disassembl ytakedown-and-upgrad e-guide/