Have the original sales contract from my car dated 03/05/1970. Sold to: William J Miller 515 So. Milwaukee Ave Wheeling, IL 537-6942 Sold at: John Mulfich Buick Inc. 801 East Rand Rd, Mount Prospect, IL. 60056
With a name like 'Bill Miller', and without a DoB or something else to pin him down by, unless he stayed in Wheeling for a huge time span; that's going to be tough. I gave it a go for about 10 mins via familysearch.org & myheritage.com, but too many William Millers...
There's a Bill Miller in Wheeling, IL on Linkedin, that lists him as retired in 2015 after working 38 years.
https://www.linkedin.com/in/bill-miller-713045a/ There is a way that "premium" Linkedin customers could message Bill Miller, but I am not one of those, and I never will be, Maybe someone on the board who has premium membership could try messaging for you?