I think you're probably right about how Jiggs got his nickname. I remember the comic strip from when I was a kid. It was already very old-fashioned then, but had a kind of nostalgia value. I had no idea it kept going till 2000...
I'm sorry route 66 never went beyond Harlem Ave.. Route 66 & 34 separated at Harlem Ave. , the little wiggly line just below where your red line starts is where Route 66 separates from Harlem and is where Route 66 comes into it's own.