Bob,
I have 335RLBS as well. I have fished wires using a steel fish tape. I removed the shrouds from around the vents in the bathroom and bedroom. From the bathroom vent I was able to get over to the entertainment area. I pulled a fish string from the entertainment center to the bathroom vent and from the bathroom vent to the bedroom vent and then over to the TV area in the bedroom. I then pulled new coax from the entertainment center to the bedroom TV area. Everytime you pull a wire, always pull a new fish string with it. I have a fish string that is in the ceiling if I ever need to pull more wires. As to the insulation, it was laying on top of the ceiling. I tried to be careful and not catch it with the fish tape. I believe I was successful. While I had the vent shrouds off I fished another pull string to the vent in the back of the coach that also goes to the entertainement area. That way if I ever need to pull a wire to the back of the coach, I already have a pull string there. Just remember to always pull a new string everytime you pull a wire. This saves you from having to fish a pull string again.
