I used the air method on an old 302 I had. I never set the engine to top dead anything. Took off the valve covers, removed one spark plug at a time each time screwing in an adapter from an old compression gauge I had, and with an air line connected with a regulator keeping the pressure to about 50 psi or so (don't remember exact amount-been a few years) backed off the rockers and removed the springs. Worked my way around the whole engine in no time and ran that puppy smoke free for a few years after that. Not a bad idea to remove the oil pan when done if you can. I found a few valves with nothing left of the old seals, guess where those pesky little pieces of the old seals went to
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[ October 28, 2002: Message edited by: dmorris1200 ]</p>