I just received a couple of iphone photos from an attendee (but I
don't have permission to post them) which clearly shows that the
thermocouple was attached to the nut near the center of the
manifold. As best as I can tell, this lines up with the center of
the connection to the heat exchanger.
http://lenr.qumbu.com/111010_manifold_001_h1200.jpg
I don't know whether the hole "C" penetrates the chamber.
In any event, this puts the thermocouple only 2 cm away from the
center-line, and the thickness of the top of the manifold looks to be
about 1 cm.
Of course, rulers haven't been invented yet, so these distances are estimates.
(Sorry, Jed ... this problem won't go away.)
