I've recently stumbled onto MotorWeek's YouTube channel and their Retro Reviews posts. These are digitized clips of segments of MotorWeek that were made and broadcast throughout the 80s and 90s, and it's quite interesting to play a game of "spot the road" and identify current and former MD State highways.
One video of particular interest is this one, where they use the westbound carriageway of I-70 at its stub end at Security Boulevard to test a 1982 Dodge Challenger. Anyone familiar with the Park and Ride at that spot can readily identify the terminus in this video, which shows it in original form sans lane markings, and with the original turnaround in place to change directions and access westbound Security Boulevard.
I'd be curious to know if there are other videos, besides this one and another one where they secured access to southbound I-795, where an existing MD state highway can be identified.
This thread has a ton of the older Motorweek reviews you speak of, you might find what you're looking for there:
https://www.aaroads.com/forum/index.php?topic=17891.0