See Inside the Illinois Route 66 Grill with Dragsters on the Roof
If I were to list all of the places that I'd recommend you'd stop by on historic Route 66, it would take days to read. There is one place in Illinois though that I was reminded is a fun location especially if you love classic cars as it's a grill with dragsters on the roof.
Not that long ago, a Midwest road trip YouTube channel visited Motorheads Bar & Grill in Springfield, Illinois. You know you've found a place that loves classic cars when their restaurant menu features an "owner's manual" section.
Their visit included a walk inside this retro-feeling Route 66 place.
If you've never been to Motorhead's, it's just off interstate 55 in the southern part of Springfield, Illinois. The reviews on TripAdvisor are generally pretty high with only a few who didn't enjoy their stop. The Yelp reviews are the same with many recommending the Road King Cheese Curd Burger.
As you're likely aware, there's a lot more to Route 66. Travel and Leisure included 16 different places that come highly recommended along this historic route including Route History in Springfield which is apparently only open by appointment now. Sad.
Motorhead's seems pretty active on Facebook if you're interested in what's happening along their part of Route 66.