Okay here's my set up, I have 4 pedals in the first 4 loops running into the front of my amp(A Marshall Jvm). I have a midi eq pedal in loop 5, 1 channel of my decimator pro rack g in loop 6 and My line 6 m13 in loop 7 and a vox time machine delay in loop 8 all running into the effects loop of my marshall.. Here in the question.. How can i set up the line 6 to run in front of my amp and in the effects loop of my amp using the 4 cable method by using the gcx.. In other words I want to still be able to use my effects pedals in the front of my anp in loops 1-4 but would like to be able to use the line 6 in front and in the effects loop as well.. Kind of like, say sometimes I would use my compressor, chorus pedals in the front and the line 6 for delays in the back but then sometimes use the line 6 say distortion models in the front of the amp and it's reverb and delay mods in the back.. I think I am over explaining but any help would be great.. Thanks..

There is an excellent .pdf document on the Line6 Support site, complete with diagrams, that explains how to configure a Multi-FX Unit and an amp using the 4-Cable Method. That should get you up and running.