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The only way to determine this is to run a compression test on both cylinders. I am willing to bet that your compression is still strong enough on the bad cylinder. Next check for spark at both cylinders. Let me know what you find and we will continue.
Your settings are Intake .006 inches plus or minus .001 inches, exhaust is .008 inches plus or minus .001 inch.
You can set the valves when they are closed, Then rotate the engine until the other valve is closed and set that one as well. Both do not need to be up to set.