I could be wrong (long time ago) but it seems to me if they are put on the wrong way the bleeder screw will not be at the top. That may be one way to tell also.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars (now converted to a "factory" 4 speed)
I could be wrong (long time ago) but it seems to me if they are put on the wrong way the bleeder screw will not be at the top. That may be one way to tell also.
I recall the same thing from my disc brake installations.