Be very careful paralleling handles on the post-war ZW, VW or KW transformers. If you have them off by a very little, the result is basically a couple of shorted secondary turns on the transformer. This makes it run very hot and also eats the carbon rollers much faster than normal. It can also actually cook the enamel off the windings and ruin the core.
Consider the following example. Note that I have made a "connection" between the B and C posts to parallel those outputs. If you look at the effective circuit, the two rollers are obviously directly connected together. Now just move one a very small distance on the core from the other one, the result is a direct short across the core windings. This is a very bad idea!
