I was copied on your post, I guess because I originated this Greyhawk mod post some time ago. Not sure if you are still looking for feedback. Maybe this could be helpful.
When we bought our Greyhawk 29me, the jackknife sofa was a pathetic piece of furniture. It was uncomfortable and small. So, the first thing we did was remove it and replace it with a powered, dual seat recliner. This was before Camping World offered their RV furniture, so we went to a major regional furniture warehouse for a good selection of replacements. If we were to do it again, we would definitely shop the Camping World recliners. Since the new recliner was more plush, and therefore larger, we had to do some mods on the slide floor.
First, I tapped into a 110v power line that happened to pass under the sofa (that was fortunate) and installed a standard outlet to power the recliner. Next, I built an interior slide extension. The front edge of the new recliner stuck out a little bit over the slide floor, so I needed to provide a floor right in front of the recliner. The recliner height was higher, so without a floor extension under the front of the chair, our feet would dangle in the air. Not very comfortable.
The slide floor extension was simply a rolling platform that attached to the slide floor and rolled along with it as the slide was extended and retracted. It was sized so that when the slides were retracted, it just nestled up against the opposite dinette slide. When the slides are extended, we simply stepped up onto the rolling platform in front of the recliner, and sat normally in the recliner. The recliner is a wall-hugger design, so it extends the footrest and reclines without impacting the exterior wall behind the recliner.
Everything has worked perfectly and offers a comfortable position for my wife and I to watch the TV on the other side of the living area. The only drawback is that the recliner is plush, and therefore larger, so it is more room-filling. The living area looks and feels smaller with such a large recliner. But comfort was more important to us.
I hope this helps. I think I included pics in the original post.