Hello. I am thinking about buying a 426 from a relative. I got it and it was very hard to start. All the time it was just a bitch to start. So some people said it probably just needs the valves adjusted. So I take it to a shop and tell them to take a look at it. They call me and tell me that it does indeed need the valves adjusted so that will be $150. Then they call me back a little later and tell me that the cam chain is stretched and to fix that and the valves will be $400. I am kinda stuck and don't know what to do. Also just wanted to know, is it shims or a rocker arm? And Is it the cam chain of the tensioner?