It would be some sort of folly to try to list all the past players of the 4th team. The one year I kept an accurate record (actually this was the 3rd team 1981-2) there were more than 120 players who turned out for the team in that one season!
I would, though, like to mention one person: Colin Howarth. Colin was a prop. I think he himself would admit that he wasn't the best player around, but he was the ultimate in terms of reliability.