Just did this a short while ago. The hardest thing for me was getting access to the where the grip wire connect into the wiring harness. PITA but you need to take off the left panel to get good access.
The grip warmers came with instructions. It took me 1 1/2 hours to install and 7 hours to find the conector behind the left front cowling. It was a tiny unmarked plug by the turn signal. The instructions where " plug in conector" :angry2: , it was the most frustrating part of the install. The warmers a def woth having.