Load balance exchange for internal Access

Hi,

I have read a number of posts on here, but none has answered the question.

I have 2 Exchange 2016 server EX01 & EX02.

I have Load Balancing setup on the external IP .226 with 2 rules, 1 for https and 1 for smtp.  These both work and thats all fine.

the Problem is that i also want the internal traffic from the same subnet as EX01/02 to be load balanced.  I have read that i need to add an additional IP to teh internal interface to act as the VIP IP, and then add a DNAT rule.  Thats the bit i dont understand.   

If the IPs are:-

EX01 has 10.1.1.14
EX02 has 10.1.1.15

Internal Interface has additional IP 10.1.1.13 for the VIP

The public Interface has an IP of xx.xx.xx.226 which is begin used by the load balance rules

What do i put in the DNAT rule to allow internal traffic to point the let load balance rules?

I am sure i have missed something important, but i just dont understand how to get the internal traffic to use the load balancer.

Thanks

Ian...