Lack of hood pins is my first wonderment as well as the moved and no cooler(just like 69 Boss 302s) There does seem to be a depression in the rubber radiator seal around the passenger side hole
Inspection stickers suggest Dearborn as well as the stapled on radiator seal. The 69s also used had the reinforced shock tower braces
Not sure what your seeing when you refer to the valve cover is missing.
69 style shock tower braces, later cast 69 - 70 valve cover style
Being a magazine car could explain the wing nuts on the top section of the shaker. So "fine tuning" of these cars was the nor to get better reviews by the writers
Looking at where the horns are located it would seem to be SCJ car ? Missing the oil cooler, using wing nuts on the air cleaner, corner of the forward-upper right C9 valve cover is missing ? The service decal on my Metuchen car is vertical. This one appears horizontal. Maybe a clue there ? The only hint that it might be a 70 are the shock tower braces. I can barely make out the extra bracing at the firewall side ? Gotta squint real hard. Brian