We had a mid-1984 Keystone and now have a 2007 Keystone. The first comment I have is that we miss the wider floor space of the 1984 Keystone. That manufacturers narrowing the tailgate openings of pickups after 1993 or so is a real shame.
We did not have a house battery in the 1984 Keystone. We had two unpowered vents (with metal lids!) in the 1984 Keystone. Our 2007 Keystone has one powered and one unpowered vent (I will be adding a new powered vent in place of the old unpowered one). We have dual 220Ah 6v batteries in plastic battery cases, in the 2007 Keystone (installed in 2017 and still going strong) along with a Victron 100/30 Solar Charger and Victron Battery (Shunt) monitor all mounted under the fold over couch (which is a different and better couch than in the 1984 Keystone). We have a 360 w solar panel on the roof. We seldom have the need for power between the truck and the camper. If I were to do the batteries over today I would probably go with a 100 Ah Lithium Ion Battery.
Since you have the insides apart I would strongly suggest having the OEM 120v - 12v power converter (I forget the brand) checked out. You may want to consider replacing it altogether.
Indeed, be sure to put a fair amount of thought and planning into the power system early in the remodel.
Consider at least one powered vent over the cooking area, we like the pressurized water system but a foot operated manual Whale pump would be OK. You may want to look into the newer fold over couch to see if it would fit. It works much better.
I am agnostic on 3-way vs 2-way Refrigerator/freezers. Our Norco 3-way in the 2007 Keystone has worked well. We pre-cool using 120v then mostly just leave it on propane (I put a wind baffle in the vest area to keep the pilot from blowing out at freeway speeds but it is trial and error to make it work). We have a 12v Dometic CSX-35 behind the front seat center console of our 1993 Dodge W250 Clubcab pickup and it works great. We do not leave it plugged in when the truck is parked for longer than a few hours. I also have a dash mounted 50 w solar trickle charger with built in charge controller to keep the truck batteries topped up since it often sets without starting for weeks at a time.
Fully recharging lead acid batteries (FLA, AGM, Gel) after discharging and not discharging below about 50% routinely are essential to maximize their life.
We have a shelf in the passenger rear corner that is just high enough to slide a porta pottie under. On top we have a plastic 4 drawer unit we bought from wall mart to store our cloths in. The setup works great! The porta potti is only used for urinating which makes cleanups easy and minimizes odors.
I hope this is helpful,
Craig
