Have the new gasket ready that goes on the head. It's a $1 part. Put a rag in the head while you scape off the old gasket to keep the scmootz out of there. Use a new hose of course. Take a good look at the fitting that comes from the water pump while you have the hose off. It may be getting ready to go too. If so there is no better time to do it! It's leaks after you shut it down because the system is still under pressure and the coolant finds the path of least resistance. I just did one last week. Don't over torque the bolts that go into the head. It's just a coolant fitting, not a moving part. I like to use grey RTV water pump sealant for any coolant areas but everyone has their favorite flavor. By the looks of the rust around the fitting I would flush the system. I see nothing wrong with green coolant. Although I do like the color Orange. I think I'm up to 10 cents now.
Oh, and have fun.

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'70 F100 shortbed
'82 Diesel Westy
'83 Euro 300TD
Curtlo Viper
Yeti ARC
Surly long haul trucker