260/289 Harmonic Balancers

["Schotland" <gary@schotland.com>]

Is the 260 harmonic balancer interchangable with one from a 5 bolt 
289 (1963 vintage)? 

I have a shop rebuilding a 289 that I yanked apart 6 years ago.  The 
harmonic balancer was missing, so I sent them one from a 260 I 
had laying around.  There's been one delay after another with them, 
so I'm not sure if they're just jerking me around because they need 
an excuse to delay things for another week or because there's an 
actual difference.

Thanks for any insight.

Gary