I've owned both SCW 1911 and Magna 1911... i think the gilded V12 was only available in Magna blowback, if, in that case refer to this diagram:
http://tech.airsoftcanada.com/WA/wa-Colt1911.jpg
you shouldn't need to take the inner barrel out of the outer barrel.
You just have to take the slide off the gun, and adjust the screw directly under the chamber, Part no.97.
Don't over tighten the screw, the female threads are made of plastic and can easily be stripped.
Hope that helps.