scook
Yes, the header is one way. In 64bit versions of SONAR, all 32bit VST plug-ins have (32-bit) appended to their name in the menus and browser. In the X3 browser the 32bit plug-ins names are green.
Only if using the "Default All Plug-ins" menu layout...
As shown below if you use a custom plug-in layout menu you loose the "(32 bit)" type ID, only the color is changed unless you use *MenuMagic or other 3rd party tool.

*Disclaimer: I created MenuMagic, so even though I am presenting this for informational purposes I do have a vested interest in this topic.
With custom plug-in menus...

*Disclaimer: I created MenuMagic, so even though I am presenting this for informational purposes - I am blatantly biased, prejudiced and non-neutral about this topic.