Your jack looks great, now get out there and rebuild him (well his neck/head). PCV and the calking should work. When you do get him fixed, put up pics of his post recovery.

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As darkness falls, the path ahead becomes veiled in gloom. A jack-o-lantern shines through the night. It's horrible visage serves two fold. To keep wickedness at bay, and remind travelers their fate, if they wander off the path.
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