Since I power my whole house with LFP batteries amid the frequent power outages in FL, it was only natural that I converted our Thor Freedom Elite 26HE to LFP.
I never liked having the house battery below the entry steps, where it gets wet, dirty and and is exposed to the elements.
So, I opened up the rearward dinette bench and reorganized the wire mess there . . .

There are 2 pairs of sturdy metal brackets to anchor the seat belts and those are perfect spots to secure 2 100A LFPs in between. Nice, dry and warm.
Since I am using Vatrer server rack batteries for my house, I went with the same company and bought 2x100A 12V batteries with integrated Bluetooth for monitoring.
I kicked the ancient battery under the entry steps out, installed a 50A fuse there instead and used the same cable, which runs to the electric department underneath the bench to connect to a Victron Orion DC-DC 50A charger.
Next step was to change the converter/charger inside the WFCO 8955 distribution center to a Lithium version.
(But not the one from WFCO itself, which $310, but an aftermarket version for 80 bucks)
Rigged the 2 batteries in parallel, installed the Victron 300A smart shunt between the negative battery side and the negative bus bar and all was running fine . . . So I thought.

When I had checked everything I remembered that we have a genset installed. Pressed the button . . . Dead.
Hhmm, now I remembered that there was a second red cable on the old LA battery, which I thought was for the emergency/jumper switch. I had it isolated with shrink wrap and zip tied to the battery tray.
That was actually the power cable to start the genset.
I just left it there. Too much effort to make a watertight connection underneath and run the cable to the batteries.
Since the genset sits almost exactly underneath the dinette bench, I drilled a half inch hole into the floor underneath the bench and ran a 4 gauge cable directly to the starter solenoid of the genset. Worked perfectly.
I measured the amperage during the startup process with a clamp meter and after an initial unreadable spike it settled to about 70 amps., which is just fine for the 4 gauge cable.
Costs:
$430 for the 2 batteries
$320 for the Orion DC-DC 50A charger
$85 for the Victron 300A shunt
$80 for the 8955 Li converter/charger
$65 for 2 ANL fuse boxes, some crimp lugs and cable.