J Tech Laser integrated with X-carve grbl (Inventables/Master version 1.0c)

Firstly Thanks Larry…next for the gcode challenged and those of us that just want to laser engrave pretty pictures…is there a Really simple explanation of not only setting the new grbl update up (I mean Mickey Mouse type illustrations) and having just purchased my laser, also confused by the wiring to the driver control. On the Jtech site they call for the spindle control wires and the 24v spindle wires to be soldered together. I ain’t connecting till I get the OK from you guys with perhaps another photo. Please…
Regards
Mike