Ah, the Interstate tank is a different kettle of fish, entirely.
I've got a NOS sample of one, its one of about half a dozen different versions that appeared.
Twin pinstripes signify an 850 version - the 750s had a single (wider) pinstripe.
Pic, selected at random.
Interstate mufflers would be lower and flatter...
There are several different versions of fork yokes.
Some may or may not work with various tanks.
It would be best if you had ones for the disk brake, and then work from there.