Yah have to hold the valve in place when you bash the keeper out.
I'd rather find a valve compressor as when the keeper & spring pop out they are quite violent, it would blind you if you got one in the eye. Serous damage even when wearing safety glasses.
At our local scrappers, they put a chain around the engine & the bucket of a digger, then lift the car up into the air & shake it till the car falls off it. Fun to watch.
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