Bought Junk Yard Engine, what to do before dropping it in? Head Gasket?

I just bought an engine from a guy that is suppose to have 101k on it. I am going to replace the rear main seal, oil pan gasket and definitely valve cover gasket. I am questioning if I should replace the head gasket also. How much more work is it? And if I do that, what about the lifters, and valve guides? How involved should I get?

im in the middle of replacing the head gasket, valve cover gasket, and manifold gasket... It's a bitch!!! But i would imagine it would be easier if the engine werent in my jeep... If its out i would def. replace the head gasket....

Well ,if you are going to have the pan off,check the bearings,and replace the oil pump,then look at the timing chain,it's a lot easier with the engine out,might as well do the head gasket,intake and exhaust gaskets if you have the bucks,then you know they are good:cheers: