Pair of 1N4007 diodes. Take the leads from pins 1 and 7 of the rectifier socket (plates) and move them to the anode (non-band) end, one on each diode. The other end of the diodes - the cathode/banded end - should join together, and that junction point is where your unfiltered B+ will come from. This is Pin 3 on the socket. From there, run over to your first filter.
You may also need a dropping resistor...300 Ohm 5W, between the rectifier output and the first filter cap.
http://www.radiomuseum.org/tubes/tube_ez80.html