just found some relevant information (regarding hot chasis'). sounds like an isolation transformer would be needed to keep it safe (along with another tranny for the fillaments). seems that its more trouble than its worth, especially considering ive got a perfectly good tranny that will be here tomorrow.
whats the best way to determine the value for a dropping resistor? would it be to determine the resistance the tube creates and use ohms law? how do you find that value? using an ef86, there is a connection between pin 8 ( i think) and the cathode, which complicates it more, as that must affect the resistance. is there a value in the datasheets of the tubes for this purpose? if so, what is it called?