Hey-hey!!!,
the 5AR4 has the cathodes tied together and attached to pin 8. One leg o f the choke goes to this pin( if you're using a 5V4/5AR4 or any of this pin 5V IDH rectifiers ).In this case the CT just gets taped off and secured.
The 6CA4 has its heater isolated from the cathode and the CT is an 'extra' part. Again secure, and tape it off.
regards,
Dogulas