At current I am running OPNSense 18.7_1 with dual wans and the gateway group set up as balanced (yes streaming movies and other downloads DOES aggregate the speed to double in balanced mode) with two DSL modems each running in bridge mode.First, you need to find out what the modem's fixed IP for maintenance is. I deliberately set my second modem's permanent LAN ip to a different subnet, eg my first modem uses 192.168.2.1 and my second I set at 192.168.1.1. Now keep track of which modem is on which wan and create a virtual IP for each wan in the same subnet as THAT wan port's modem, I used 192.168.2.2 on wan1 and 192.168.1.2 on wan2 as virtual IP addresses. I set two firewall rules in Floating Rules that allow lan net (I don't want wlan to access the modem) to go to 192.168.2.1/32 and a second rule to 192.168.1.1/32. The subnet only allows access through the wans to that IP only irrespective of the actual wan ip to access the internet. Then I set my NAT outbound to hybrid and added two rules, one for each wan that sets the destination address to single host using the network rather than a specific ip eg 192.168.2.0/30 and 192.168.1.0/30 for the second rule. In the Translation Target you will see the virtual WAN IP you created for that WAN in the dropdown menu for that wan. Select it, save them and you're done! I should note that with a single wan, I was able to access the modem with only a virtual IP and through the proxy. The proxy is useless in a multiwan balanced gateway group and I really have no need otherwise.