Woah, yeah, 2 Ohms there is a problem.
When you touch your meter probes together, do you also get about 2 ohms?
Are any of the 1N5820 diodes touching the terminals on the OT-2? That is about the only way I can think of a short migrating in, of course you could always accidentally have something other than the red wire and 1.5uF cap going to that terminal as well, but I think you've ruled that out.
-PB