Also, consider using oversized residential exterior plastic J molding for easy to service "open conduit" of sorts. The large size is typically not carried in big box stores. Available at roofing and siding supply houses in 12' lengths.
The pliable J molding is captured by the benchwork frame in my off scene staging room. This molding is easy to flex open for servicing your wires. I use it also for a computer cable run.
Just run it along the outside bottom edge. Relieve yourself of crawling underneath.
