I have peering setup for one of my public ip subnet for one internet connection. I have some customers with private ip addresses on the same network and I have a second internet connection and fail over setup. What I would like to do is have the private ip addresses use the second internet connection first. This will allow me to do a little load balancing. The second internet connection doesn't have peering setup. Does anyone know how to make this happen? Thank you

Not sure what you mean by "peering setup".

You can have the same routes in multiple routing tables but with different priorities. In routing table A (the default one called main), route via WAN 1 has higher preference (lower distance) than the route via WAN2, so the one via WAN 2 is only used if the one via WAN 1 is down. Now you add a routing table B, where a route via WAN 2 will have a higher preference than a route via WAN 1. If you currently only monitor the transparency of the path via WAN 1, you have to add that monitoring also for WAN 2 so that the clients at private addresses could start using WAN 1 if WAN 2 goes down.

And then you use firewall mangle rules or ip route rule items to make the clients at private addresses use routing table B.

There are tens, if not hundreds, forum topics on the same subject. Look for "policy routing", "routing-mark", "lookup-only-in-table" keyphrases.