termination and cabling question

[Sheldon E. Newhouse]

Hello,
 I have an AHA2940UW controller. There are three ports on the
contoller. Internal 68 pin, internal 50 pin, and external 68 pin. 

I have the following setup.

   tape drive on external 68 pin,
   UW disk on internal 68 pin
   scsi cdrom on internal 50 pin. 

Auto-termination is enabled. There seems to be no need for external
termination.   

On Net Express' web site there is a statement about the need to have a
linear topology instead of a branching topology for the cabling. They
suggest that all devices should be on the same cable, so that, e.g. one
should have

  tape -> contoller -> internal scsi disk -> internal cdrom)

Mine is 
  tape -> controller -> internal scsi disk (all 68 pin connectors
             |
            \ /
          50 pin internal cdrom

For the first setup, I would need an adaptor since the internal disk is
68 pin and the internal cdrom is 50 pin. 

It is working as is.  In private e-mail, they suggested that this is not
scsi compliant and may lead over several months to damage to the
hardware.  

I am seeking other opinions and/or experience.

Would it help to put an active terminator on the end of the external
tape drive?   Is it really better to simply get the adaptor for the
internal 50 pin connector? 

Thanks for any information. 

-sen