Head gasket repair 2007 ford edge 3.5L duratec 35 engine

[daveknapp2000]

Hello, was wondering what parts should be replaced with the head gasket that makes since?

 

Head gasket and thermostat make since to me and perhaps serpentine belt. what about water pump and others?

2007 ford edge with 150K miles on it.

 

When should I plan to rebuild the engine...300K?

[daveknapp2000]

Should I replace both head gaskets or just the one that blew with 150K miles. I was thinking both since I am already there. How long should this repair take for planning purpose? I was thinking an entire weekend should do it.