I installed a classic update from AAW also. Here's what I've done, and it's in anticipation of heavy amp draw.
I ran a 4 gauge alt wire. I bypass the starer and go straight to the battery. I have a 200 amp breaker inline to the bat. I also grounded the crap out of everything winch related with heavy gauge welding wire. I know you're not running a winch but this is my deviation from stock. I would go ahead with their instructions if no need to deviate. Then you will have instructions to pass on to the next owner, or even yourself a few years down the road. But I'm always a fan of overkill whenever I have my hands on someting... But I often find myself scratching my head a few years down the road wondering why I did things off the beaten path!
j