[Collins] output tubes

[yash at aol.com]

Moveing along on my KWM-2A project,I started looking ay the output 
tubes . The rig has 6146B in it now. I went to several site and found 
the
6146W was a good replacement. Then reading another site.the 6146 W was 
a BAD choice. Got the same answer from several of the listed vendors 
,but no real facts.
    Since I have to replace the existing outputs ,what verson of the 
6146 SHOULD I be using. Iam confused with all the differant answers so 
I thought I would as here ,for the right one.
thanks for the help
dale wt4t