In any guitar wiring situation, it's good practice not to have multiple ground paths, so make sure there aren't any loops in the ground wiring. Star-wiring grounds to a single point is best, but not always practical, otherwise use a branching ground system with no loops.

Make up a wiring harness using the minimum lengths of cable necessary. For the longer cable runs (and with the distributed control arrangement on the GR1-SF there are several) it is best to use shielded cable to minimise noise pickup.