The game plan is going to be just pull out the bottom 45AMP module and keep the 120VAC and 12VDC Distribution panels in place. This will only require just a few wires to connect up. If you replace the whole assy you will have to pull all of the wiring out and re-wire into a new Power Distribution Panel unit. Lots of wiring goes to this panel.
This is a couple of photos from google search but once you know the exact models concerned you will find a complete retrofit on-line on what you need to do. The best thing to do is get in touch with BEST CONVERTERS and have them walk you thru what you need to buy and how to retrofit it. Keep in mind these google photos are NOT your model but just showing the concept involved here of changing out the converter/charger module... I would stay away from the WFCO converters/chargers - they have a track record of not going into smart mode charging when you think they should be doing. AT least I had that problem with my WFCO 8900 series unit...
I use the smart mode Progressive Dynamics PD9260C replacement model here in my setup. I however have three deep cycle batteries in my battery bank (255Ahs capacity) to take care of... Smart mode converters/chargers is the way to go and once installed will take every good care of your installed deep cycle battery.
Roy Ken
