The following is a suggestion only. It may will be that continuing with our current pickems is preferred option of forum members.
eWRC-results.com website has a pickems section where you need to predict top 10 drivers for each WRC event. In addition for each round you need to pick top 3 from a support category. Could this be used for our forum pickems ?
Advantages - (1) it already provides a results calculation system (2) it is free to join (3) it has a groups functionality and we could be a group
Disadvantages - (1) it uses a different scoring system (2) each group is limited to 50 players.
Here are the rules for eWRC pickems http://www.ewrc-results.com/pickems_rules.php