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Wednesday 22 November 2017 at 04:45
Put the pop bumper screws in by hand as far as they’ll go and use a nut and nut driver from under the PF to slowly draw them in if using a hammer isn’t your cup of tea.
Source: http://pinside.com/pinball/forum/topic/vids-guide-to-ultimate-playfield-restoration/page/105#post-4085717