Hi, new forum member first post. Just starting my OTS build. I hate to say this, and maybe I'm wrong but looking at the pics in the first post in the thread, I think you've used the wrong wire for the heaters. If you check out the pic here: http://www.ceriatone.com/images/completeAmpsPic/CTOvertone/c11B.jpg and other pics of amp internals, you'll see that heavier gage wire is used for heaters. Understandably they must be required to conduct a fair amount of amperage, because they are after all the tube heaters....

Edit:The insulation on the wire supplied as "heater wire" on the parts list is much thicker, but the actual internal wire itself is just a little larger than that of the supplied black and white wires. So this may not be a big issue...