Jase it was done at 1790mm and f/9 with the TAL200K. The EQ6 with belt drives and the Bartels system has no problems accurately tracking even at this FL. There is NO (discernible) backlash as the mount has been adjusted to within a tad and shown the firing squad just in case. The only regret I have is that I had the wrong spacer (thin) in the Hutech FR/FF so there is a bit of field curvature.
Here is an image with the correct spacer but focus went slightly off with a very large drop in temperature.
http://members.optusnet.com.au/~fmlee/30dor_tal.jpg
Bert