In addition to euro 287's excellent advice, I would put a bit of oil on the underside of the head bolt where it contacts the head bolt washer. Oiling there will ensure that friction is not impeding the movement of the head bolt as you're turning it so that you get a true 90 degree turn so the bolt will stretch correctly.

Good Luck!
Tom

__________________
America: Land of the Free!

1977 300D: 300,000+ miles

American Honda: Factory Trained Technician & Honor Grad.
Formerly:
Shop Foreman;
Technical Advisor to Am. Honda;
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