Hello Bobcat!…. The tilt steering column Studebaker used in Avantis, as well as the tilt column used in early ‘A’ series Avanti ll’s, was a tilt column common to mid sixties GM vehicles ( Buick, Olds ) and although replacement parts from those GM tilt columns will interchange with the tilt column Studebaker used, the columns themselves are not directly interchangeable.
Around ‘70- ‘71, when the ‘B’ series Avanti ll’s came to be, an entirely different tilt steering column was used.
This later (Saginaw) column had the ignition switch mounted in the column, and is still very common these days, as it was used in ‘B’ series Avanti’s at least thru ‘85, and also used in ‘70-‘90+ GM, Chrysler, and AMC vehicles.