What "model" of FunFinder? Usually there's number after the X? Like the 210UDS or 189FBS ? With the 2012 you probable just need to remove all framing from the dinette seating and decide what to do? Meaning the floor of the slide makes it easy to just put in a "store bought" loveseat that flips to a bed? Maybe a futon? Or you can search RV sites for the RV sofa setup that requires a frame and the upper part of the sofa. They're not cheap. I've got some pics of a DIY sofa/bed if you're interested.
2012 FunFinder X 210UDS
4-68 watt flexible panels; 1-215 glass panel/4 Battle Born LiFePO4 Deep Cycle Batteries
2014 Ford F350 6.7 Liter PowerStroke V-8 Diesel longbed, SRW