Where's the Skills Gap?

Tyler Cowen spotlights a blog post presenting some analysis suggesting that the US economy, and particularly the goods-producing part of it, is experiencing a skills gap--firms want to hire people with skills that are not available among the unemployed, or among discouraged workers.  The author reaches this conclusion "...the US has gutted its manufacturing base, creating a large deficit of skilled manufacturing workers. The skills gap therefore is likely to persist for years to come, creating a material drag on economic growth."    It's worth looking at the analysis, and the evidence presented there.

The evidence there is substantial, and has to be considered.  But I think there's some other evidence that should also be considered:  What's happening to average weekly hours, to overtime hours (among workers with overtime), and to real average hourly earnings.  Using BLS (monthly, not seasonally adjusted) data, here's what I find:

(Click each diagram to enlarge.)

All three show essentially the same pattern--declining weekly hours and weekly overtime during the recession; declining average hourly earnings during the recession, all followed by recovery and then plateauing around 2010 or 2011.

This is not, it seems to me, consistent with a skills shortage.  Firms would want to extend the hours of existing workers, offer more overtime, of offer higher pay.  Yet none of that seems to be (systematically) happening.  If there is a skills shortage, why is it not showing up in these data, in addition to the data in the post I've linked to above?