I wired it up like this:
Being as resourceful as possible I used a cd-rom audio cable since I only needed to work off two pins and I had one just laying around and the pin holes happened to be perfectly spaced.
I just had the script start running after the service that I was concerned about starts.
while :; do echo 'null' > /dev/ttyS1; sleep 0; done &
This results in an infinite loop of 'null' to be sent to the serial, causing the light to stay on.
Hope this info helps someone!