Gotcha! How can i have the gt8 in 2 loops for left and right if there is only one input on gt8? I guess what i am asking is how to wire gt8 so i can bypass it and still have left and right work as if left goes to one amp and right goes to another.
I'm quite sure the GT8 (and the G-Major as well) converts Mono Input signals into stereo Outputs, so you only need to send a single source to either of these units, then run the Left and Right Outputs to two GCX loops. Not knowing what else your rig consists of, here's a simple method of making this work.
If you have your guitar running into the Guitar In on the front of your GCX, connect the Guitar Out on the GCX rear panel to the In jack of Loop 1. Connect the Loop 1 Send Jack to the Guitar Input of the GT8, and the Loop 1 Out Jack to the Left (Mono) Input of the G-Major. This will make the G-Major your default FX Processor; activating Loop 1 will bypass the G-Major and send your guitar signal to the GT8. Since, as previously mentioned, the G-Major will convert the Mono Input signal to Stereo Output, there's no need to run a guitar signal to the Right Input of the G-Major.
Connect the Left and Right Outputs from the G-Major to the In jacks of Loops 2 and 3. This makes the G-Major the default signal feeding these loops respective outputs, and in turn, your amplifiers.
Connect the Left and Right Outputs from the GT8 to the Return jacks of Loops 2 and 3. When these loops are active the G-Major is bypassed and the GT8 signal is routed to the loop outs, and then to your amps.
Connect the Out Jacks of Loops 2 and 3 to the Inputs of your two amplifiers. Be sure to keep the Left and Right channels in the proper paths.
Let me know how this works out for you...
To make all this work, you'll need to program Loops 2 and 3 to come on when Loop 1 is activated. As you recall, activating Loop 1 bypasses the G-Major and sends your guitar signal to the GT8, so activating Loops 2 and 3 will bypass the G-Major in those loops as well, feeding the GT8 signal to your amplifiers.