Don,  I suspect your Conn 6T3 is really an ST-3.  Suggest you pick up
the documentation for the ST-6 off my personal web site.  Just click
on the image of the ST-6.

     http://www.mts.net/~smythe/conn.htm

Basically, the ST-2 through to ST-8 Strobotuners were very similar
to one another.  I've had an ST-2, ST-4 and ST-6 pass through my hands,
and other than the color of the case, I've not been able to detect any
noticeable difference.

Some years back I acquired an ST-6 with its complete documentation,
so decided to scan it and post it on my personal web site for others
to use.  It serves me exceedingly well.  Hope you find it useful.

Regards,

Terry Smythe
Winnipeg, MB, Canada
http://www.mts.net/~smythe