Load Balancing over two public IPs

Hi
i want to do a Load Balancing over two public IPs
I have a two internet connection with public 2 IPs for each connection, and i have a two server with private IPs
i do load balancing same as http://wiki.mikrotik.com/wiki/Load_Balancing_over_Multiple_Gateways but from outside the private LAN i can’t connect to the router also to a server2 please help me
i do the destination NAT but not working for me
this is the architecture of my private network