I just assumed that "41" refers to US Route 41, which runs almost straight down the middle of the Continental United States, from Michigan to Florida. The lyrics say that he's "stayin' clear of the Interstate," so it can't be a main highway. But he mentions farms and fields, which invokes the Midwest. The song implies he just got in his car and just drove all night. US-41 runs for 2,000 miles from end to end; plenty long enoguh to just drive.
I just assumed that "41" refers to US Route 41, which runs almost straight down the middle of the Continental United States, from Michigan to Florida. The lyrics say that he's "stayin' clear of the Interstate," so it can't be a main highway. But he mentions farms and fields, which invokes the Midwest. The song implies he just got in his car and just drove all night. US-41 runs for 2,000 miles from end to end; plenty long enoguh to just drive.