Cart numbering

Hi, Is there a way I can change the Cart numbers so I can match them to the numeric kets assigned to fire them?
i.e. change cart 1 to 7, cart 2 to 8 and so on?

Any help welcome.

It is: Reassign commands for Nos. 1 to 3 and 7 to 9 to CART 1 START and so forth and install following background script:

procedure OnExecuteCommand(Command: string);
begin
  if Command = 'CART 1 START' then
    ExecuteCommand('CARTWALL 7 START')
  else if Command = 'CART 2 START' then
    ExecuteCommand('CARTWALL 8 START')
  else if Command = 'CART 3 START' then
    ExecuteCommand('CARTWALL 9 START')
  else if Command = 'CART 7 START' then
    ExecuteCommand('CARTWALL 1 START')
  else if Command = 'CART 8 START' then
    ExecuteCommand('CARTWALL 2 START')
  else if Command = 'CART 9 START' then
    ExecuteCommand('CARTWALL 3 START');
end;

begin
end.