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We do not remove the engine when we do these head gaskets and you can but to us this is more work. Labor time by gm to do both heads on this vehicle is around 24.0 hours. Its not a hard job but time consuming because of the little things, like fuel lines, washers and bolts. There is 22 head bolts on each side and when you do this ensure to torque them correctly. The hardest part of this job to me is the exhaust. If you do this and when you get started let me know and I will walk you through it. If you decide to pull the engine, it will be easier on the ground but take longer. Let me know what you decide and good luck. If this info helped please click on accept.