Pretty simple actaully, removing the bar end is actually the hardest if you've never done it before.
In case you haven't, I wrapped a web strap around the b ar end with a pair of vise grips and used it like a oil filter wrench while turning the screw. Those damn things are tight the first time you ever try to remove them.
After that, theres simply 2 bolts in the bottom of the switch assembly, remove them and the housing opens up and the grip is right there. Just remove the throttle cables and it free.
Shouldn't take more than 5 minutes if the bar end comes of easy.