Hi Rob,
There's no original Macdonald left as far as can be determined. Not all of the course actually sits on the original footprint of the course. Some of it does, but the original CGC was on leased land, and when CGC moved to Wheaton, the land was leased by Illinois Golf Club. It eventually folded, and when Belmont Golf Club came along a couple of years later, not all the original land was available. The course was reworked, and has subsequently been remodeled three times since (1976, 1994, 2003). The Belmont version with back-to-back starting par 3s was eliminated in favor of a par 4 in 1994, with a par 3 added elsewhere.