[flatjack9]

Pulling the valve spring down will not release the guide lock. You need some special tools for doing the job. By the looks of the valve keepers, you have the mushroom stem valves. Makes things harder. There is a notch in the valve guide near the end of the small diameter that is meant to be engaged with a special tool. This is used to pull the guide down allowing the removal of the guide keeper. Then the assembly is pryed upward and out. There is also a tool that can be inserted in the hole in the guide retainer that can be used to pry the retainer out. Probably the easiest method.