Moparboy01

I got a buddy who has a 96 Jeep Grand Cherokee, with a 5.2L in it. He has been having some motor problems lately, so today I went over to take a look. Now being a Jeep mechainc he thinks I could fix everything (wish it was that case sometimes). Anyways, I noticed that when he stepped on the gas pedal or I pulled the throttle cable the camshaft would walk out and kill the motor. I am thinking that it must be the thrust bearing. Has anyone ever done one of these? Is there a link to showing how to replace on of these. My buddy wants me to fix it and I told him, I have never really done one of these before but he wants me to fix it anyways. If anyone could help that would be great