question about 1993 Astro steering column

Hi, all, I have a question. We have a 1993 Chevrolet Astro with a 4.3 engine. The steering column is broken and we can't fix it, something is broken inside. We took it apart and tried to tighten the star shaped bolts, but it is still loose. We called a local salvage yard and they said only a steering column out of another 1993 Astro or Safari will work, not a 1992 or a 1994, a 1993 only. Does anyone know why only a 1993 will fit? I am very confused by this, they all look the same. Thanks for your help.

I changed out a 94 safari with a 93 astro and it looked like it had been changed from a Chevy truck it said Chevy truck on the front horn button dont know the year looked like my 97 i think they are all the same ... it was 75 bucks at the pick and pull