Hello all!
I have a 1989 24' Funchaser and am replacing the dry rotted bonded plywood "2x4" on the driver side front. After cleaning out the area and re-shaping the metal, I decided to install a pressure treated 2x4 cut to length but ran into a dilemma. How did they run the wiring through the bonded plywood and retain strength? I thought I would use a router and cut a channel but which side and would it compromise the board? Do I rip the board, router both or one half to create a channel to run the wires in? I am sure I am overthinking this but I have seen posts where people do partial epoxy fills and I am trying to avoid that mess as there is no board left to resin fill. Also resins are like glass and can shatter.
Any thoughts or ideas are gratefully accepted!!

I have yet to do this needed job on mine, but are you asking lift cable or electrical wire, if cable, i would put 2 bys on both sides of the pully, overkill yes but sturdy

Thanks for replying, it is actually replacing the wood inside of the sheet metal cover around the bottom edge of the top half. I see where the bolt for the cable screws into the metal frame but the wood that the cable goes around and up to the pulley has rotted out, I'm trying to replace it with some pressure treated wood but running into all kinds of difficulties like where does the wiring go in the wood? I did talk to a gentleman that used to build them back in the day at J&R and he said to use plywood or to router a trough through the board to set the wires in. Tried that and could not get it to work. His other suggestion was to rip the bored down the edge of the routered trough and insert it half at a time and glue together. So far I have the bottom half three quarters of the way and now it's stuck and will not come out. It will not go in either. I have my ex-wife's boyfriend who owns his own RV repair shop coming out to look at it today and see what he thinks and whether or not he wants to take on the project as it looks like it's beyond my pay grade.