Internet traffic one connection, SMB on other

[bigmiketech]

I am attempting to setup a new netgate and figured I would ask the community. We have a 100Mb WAN internet connection, and then we have a secondary 10Mb connection already in place that is already setup via ISP to route to the main server location, so a VPN is not needed/already in place externally. For right now this other location already gets it IP addresses from main servers through this 10Mb connection, but soon we will be placing this netgate so internet bound packets uses the much faster connection straight out.
I am trying to setup the netgate with pfsense so all internet bound traffic is routed through WAN, and all SMB traffic through OPT1. The only way I could think of is add firewall rules for ports 137-19 and 445, blocked on WAN, and allowed on OPT1. I am unsure if there would need to be any other DHCP specific rules needed to allow this routing
I know the basics about pfsense but this is more advanced thus I am looking for help.