How to replace siding on my chimney?

Ok, i was replacing the siding around my chimney. I have about 1 foot of roof space to work on. My latter doesn't reach high enough from the ground. This is the problem on two sides of the chimney. I don't want to do anything that will make me fall. Any suggestions on how to reach the top portions? I need to be able to reach about an additional 8 feet about my head on a slanted roof of 35 degrees angle.