The MIDI connections are typical.

The GR33 family works by triggering MIDI notes, then quickly pitch-bending to the exact tone as the pickup is tracking the string vibration.

If you look at the recorded MIDI in a sequencer, you will probably see the initial note triggered to often be the wrong note (play an "E" on your guitar and the initially triggered note could be a "D") which is then pitch-bent to the correct note as the note sustains. This process is very fast and unnoticable in realtime playing.

Because the GR series work this way, they are set up with a pitch-bend range of ±12 semitones to accomodate the quick-triggering compensation AND string bending techniques on a guitar.

•••IMPORTANT•••
Most external sound modules are set up with a pitch bend range of ±2 semitones. In order to get them to track well with a GR, you need to set the pitch bend range to ±12 semitones on the receiving module. This is generally a global parameter but on some modules it can be a patch parameter.