This is such a smart DIY with the pins attached to ropes from the standing point, forming a pulley pin reset system, so they can be pulled into place from the other end of the lane, with all the positions been located by drilling holes on the board cover!! Looks simple though it will take some time to adjust the system, level the boards before make it works.
See the step by step build here…
Imgur: DIY Backyard Bowling Alley Build Photos