Might want to decide up front if you want to allow a recency bias or not.
I'm of the opinion that almost all modern day athletes would blow the doors off of the old-timey fan favorites, if for nothing more than advances in training, nutrition, etc. And, frankly, we have the entire pool of talent in more modern times which gives us a better creme da la creme. Prior to a certain point, we only had the white kids, and the best of a smaller population almost certainly isn't going to produce the caliber of athlete as will the best of a larger population.
Others, of course, prefer to rank players according to their time, i.e., how good they were for their day. Which is really hard, I'd think, since we don't have a lot of footage to evaluate for that.