You need this.
KD part number 901. $6.80 on Amazon.

You also need an air compressor, and an air fitting for the KD tool.
Screw tool into spark plug tube and turn up air pressure. This holds valves in place when you remove the valve springs.

You will also need a valve spring compressor.
KD has a couple. Model # 2078 is on Amazon for $27.92.

Bob

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