Well, Magnum hops (or any high alpha) weren't a thing, and the old beer was definitely made from standard 6 row and corn grits, if you want the 70s- early 80s beer. Which was damn good if I may say so. When they changed the recipe was one dark day. I made a beer that really reminded me of it once. I know I used a blend of old timey American aroma hops, of the sort with old world parentage, for a modest amount of bitterness, and the bulk of the hops mid boil, a small amount FWH, and about 20% at knockout -- a very conventional American hop schedule. Grain bill for a clone? Stroh's was a little fuller color and maltier flavor than some, maybe ~20% of Vienna with basic US 2 row base malt and corn flakes in some proportion would get there. But Stroh's as I remember it had a distinct, delicate hop presence compared to competitors. Something like that hop schedule would probably make a contribution to cloning it. I look forward to other people's ideas. I'd put a decent Stroh's clone in heavy rotation in my brewery!