You will only have to replace the converter/charger unit. Most likely can keep the WFCO Power Distion Panel where all the circuit breakers and DC fuses are located. The PD series will fit in the same compartment where the WFCO converter is located. If it doesnt then you can mount the PD UNIT almost anywhere. All it needs to operate is a 120VC standard wall plug. Then of course have the three DC CABLES connected to proper termianl lugs on the 12VDC FUSE PANEL board.
When I finally decided to replace my WFCO COnverter I got the PD9260C unit and mounted it right before my BATTERY SWITCHES which is about five feet away from the battery bank. Then I used the existing DC cables coming the WFCO panel to tie into the PD9260C dual DC lugs. I used 4AWG cable to feed the battery switches I have installed for my battery bank of four each 12VDC 85AH batteries switched in parallel. I also left the WFCO COnverter unit in place as I didn't have the heart to throw away a almost brand new unit. It serves well as a back up converter/charger unit now. I can select which WFCO or PD converter to use by flipping the corresponding 120VAC circuit breaker.
Your batteries will love you for this mod big time...
When you search back on the WFCO products you will find almost all of the posts all say the same thing about the WFCO not charging your batteries properly...
I have never really figured out why the WFCO units don't work. It seems that almost every new RV units comes out with one of these converters installed.
Roy Ken