About about jtag and rgh

I havehbeen researching on how to jtag and rgh xbox 360 l downloaded jrunner program and I came across how to install coolrunner rev c that is wire install and I couldn’t understand the following.please need help because I don’t want to get help from outside.which are as follows

1)Can you use a coolrunner rev c on a phat xboX 360 direct installation without qsb?
2)I don’t understand what it means by default (jumper closed) alternative (jumper open)
3) what’s the difference between rgh1 and rgh2?
4) And how to go about rgh1 and rgh2 on both phats and slim
5)rgh1(jumper closed) and rgh2(jumper open)