How to assign multiple public facing IPs to Load Balancer NAT rule to same port

I'm currently in the process of setting up multiple SSLs on a load balancer so the incoming rules would be mapping port 443 to an internal port which I setup sites to.

This is fine as this causes the unique nature of the SSL as selects the site which needs to be served. The problem comes when I want the site to be served over port 80 on the internal box as you can't have a NAT rule which applies to multiple front end IP configurations.

i.e.

172.168.34.250:80 -> 10.0.0.1:80 Internal box (website 1)
172.168.34.251:80 -> 10.0.0.1:80 Internal box (website 2)
172.168.34.251:443 -> 10.0.0.1:8000 Internal box (website 2 SSL)

In the documentation (https://msdn.microsoft.com/en-us/library/mt619382.aspx?f=255&MSPPError=-2147217396) it states that the FrontendIPConfiguration is a List of configuration points but then it states the parameter is an object of type PSFrontendIPConfiguration