[Jim Dutridge]

My suggestion is to remove all tubes and lamps. Throw the transformer on a variac and slowly raise the voltage in increments of 10 volts while monitoring the current draw. 

Your looking for basically zero current with no erratic changes in current as the voltage is increased up to the operating voltage stated for the radio. Let it run for about 15 minutes and if you don't see the current movement as previously mentioned you should be good to go.